Data on Determinants Are Needed to Curb the Sedentary Epidemic in Europe. Lessons Learnt from the DEDIPAC European Knowledge Hub.

Societal and technological changes have resulted in sitting being the dominant posture during most activities of daily living, such as learning, working, travelling and leisure time. Too much time spent in seated activities, referred to as sedentary behaviour, is a novel concern for public health as it is one of the key lifestyle causes of poor health. The European DEDIPAC (Determinants of Diet and Physical Activity) Knowledge Hub coordinated the work of 35 institutions across 12 European member states to investigate the determinants of sedentary behaviour. DEDIPAC reviewed current evidence, set a theoretical framework and harmonised the available epidemiological data. The main results are summarised. The conclusion is that there is a dire lack of data that is exploitable across Europe to inform policy and intervention. There is an urgent need to develop international data collection compliant with FAIR (Findable, Accessible, Interoperable, Re-usable) and standardised surveillance systems for sedentary behaviour.

Correlates of sedentary time in different age groups: results from a large cross sectional Dutch survey.

BACKGROUND: Evidence shows that prolonged sitting is associated with an increased risk of mortality, independent of physical activity (PA). The aim of the study was to identify correlates of sedentary time (ST) in different age groups and day types (i.e. school-/work day versus non-school-/non-work day). METHODS: The study sample consisted of 1895 Dutch children (4-11 years), 1131 adolescents (12-17 years), 8003 adults (18-64 years) and 1569 elderly (65 years and older) who enrolled in the Dutch continuous national survey 'Injuries and Physical Activity in the Netherlands' between 2006 and 2011. Respondents estimated the number of sitting hours during a regular school-/workday and a regular non-school/non-work day. Multiple linear regression analyses on cross-sectional data were used to identify correlates of ST. RESULTS: Significant positive associations with ST were observed for: higher age (4-to-17-year-olds and elderly), male gender (adults), overweight (children), higher education (adults ≥ 30 years), urban environment (adults), chronic disease (adults ≥ 30 years), sedentary work (adults), not meeting the moderate to vigorous PA (MVPA) guideline (children and adults ≥ 30 years) and not meeting the vigorous PA (VPA) guideline (4-to-17-year-olds). Correlates of ST that significantly differed between day types were working hours and meeting the VPA guideline. More working hours were associated with more ST on school-/work days. In children and adolescents, meeting the VPA guideline was associated with less ST on non-school/non-working days only. CONCLUSIONS: This study provides new insights in the correlates of ST in different age groups and thus possibilities for interventions in these groups. Correlates of ST appear to differ between age groups and to a lesser degree between day types. This implies that interventions to reduce ST should be age specific. Longitudinal studies are needed to draw conclusions on causality of the relationship between identified correlates and ST.

The SOS-framework (Systems of Sedentary behaviours): an international transdisciplinary consensus framework for the study of determinants, research priorities and policy on sedentary behaviour across the life course: a DEDIPAC-study.

BACKGROUND: Ecological models are currently the most used approaches to classify and conceptualise determinants of sedentary behaviour, but these approaches are limited in their ability to capture the complexity of and interplay between determinants. The aim of the project described here was to develop a transdisciplinary dynamic framework, grounded in a system-based approach, for research on determinants of sedentary behaviour across the life span and intervention and policy planning and evaluation. METHODS: A comprehensive concept mapping approach was used to develop the Systems Of Sedentary behaviours (SOS) framework, involving four main phases: (1) preparation, (2) generation of statements, (3) structuring (sorting and ranking), and (4) analysis and interpretation. The first two phases were undertaken between December 2013 and February 2015 by the DEDIPAC KH team (DEterminants of DIet and Physical Activity Knowledge Hub). The last two phases were completed during a two-day consensus meeting in June 2015. RESULTS: During the first phase, 550 factors regarding sedentary behaviour were listed across three age groups (i.e., youths, adults and older adults), which were reduced to a final list of 190 life course factors in phase 2 used during the consensus meeting. In total, 69 international delegates, seven invited experts and one concept mapping consultant attended the consensus meeting. The final framework obtained during that meeting consisted of six clusters of determinants: Physical Health and Wellbeing (71% consensus), Social and Cultural Context (59% consensus), Built and Natural Environment (65% consensus), Psychology and Behaviour (80% consensus), Politics and Economics (78% consensus), and Institutional and Home Settings (78% consensus). Conducting studies on Institutional Settings was ranked as the first research priority. The view that this framework captures a system-based map of determinants of sedentary behaviour was expressed by 89% of the participants. CONCLUSION: Through an international transdisciplinary consensus process, the SOS framework was developed for the determinants of sedentary behaviour through the life course. Investigating the influence of Institutional and Home Settings was deemed to be the most important area of research to focus on at present and potentially the most modifiable. The SOS framework can be used as an important tool to prioritise future research and to develop policies to reduce sedentary time.

Longitudinal Relationship Between Sitting Time on a Working Day and Vitality, Work Performance, Presenteeism, and Sickness Absence.

OBJECTIVE: The aim of this study was to explore the longitudinal relationship between sitting time on a working day and vitality, work performance, presenteeism, and sickness absence. METHODS: At the start and end of a five-month intervention program at the workplace, as well as 10 months after the intervention, sitting time and work-related outcomes were measured using a standardized self-administered questionnaire and company records. Generalized linear mixed models were used to estimate the longitudinal relationship between sitting time and work-related outcomes, and possible interaction effects over time. RESULTS: A significant and sustainable decrease in sitting time on a working day was observed. Sitting less was significantly related to higher vitality scores, but this effect was marginal (b = -0.0006, P = 0.000). CONCLUSIONS: Our finding of significant though marginal associations between sitting time and important work-related outcomes justifies further research.

A systematic review of correlates of sedentary behaviour in adults aged 18-65 years: a socio-ecological approach.

BACKGROUND: Recent research shows that sedentary behaviour is associated with adverse cardio-metabolic consequences even among those considered sufficiently physically active. In order to successfully develop interventions to address this unhealthy behaviour, factors that influence sedentariness need to be identified and fully understood. The aim of this review is to identify individual, social, environmental, and policy-related determinants or correlates of sedentary behaviours among adults aged 18-65 years. METHODS: PubMed, Embase, CINAHL, PsycINFO and Web of Science were searched for articles published between January 2000 and September 2015. The search strategy was based on four key elements and their synonyms: (a) sedentary behaviour (b) correlates (c) types of sedentary behaviours (d) types of correlates. Articles were included if information relating to sedentary behaviour in adults (18-65 years) was reported. Studies on samples selected by disease were excluded. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42014009823). RESULTS: 74 original studies were identified out of 4041: 71 observational, two qualitative and one experimental study. Sedentary behaviour was primarily measured as self-reported screen leisure time and total sitting time. In 15 studies, objectively measured total sedentary time was reported: accelerometry (n = 14) and heart rate (n = 1). Individual level factors such as age, physical activity levels, body mass index, socio-economic status and mood were all significantly correlated with sedentariness. A trend towards increased amounts of leisure screen time was identified in those married or cohabiting while having children resulted in less total sitting time. Several environmental correlates were identified including proximity of green space, neighbourhood walkability and safety and weather. CONCLUSIONS: Results provide further evidence relating to several already recognised individual level factors and preliminary evidence relating to social and environmental factors that should be further investigated. Most studies relied upon cross-sectional design limiting causal inference and the heterogeneity of the sedentary measures prevented direct comparison of findings. Future research necessitates longitudinal study designs, exploration of policy-related factors, further exploration of environmental factors, analysis of inter-relationships between identified factors and better classification of sedentary behaviour domains.

Cross-cultural adaptation of the Individual Work Performance Questionnaire.

BACKGROUND: The Individual Work Performance Questionnaire (IWPQ), measuring task performance, contextual performance, and counterproductive work behavior, was developed in The Netherlands. OBJECTIVES: To cross-culturally adapt the IWPQ from the Dutch to the American-English language, and assess the questionnaire's internal consistency and content validity in the American-English context. METHODS: A five stage translation and adaptation process was used: forward translation, synthesis, back-translation, expert committee review, and pilot-testing. During the pilot-testing, cognitive interviews with 40 American workers were performed, to examine the comprehensibility, applicability, and completeness of the American-English IWPQ. RESULTS: Questionnaire instructions were slightly modified to aid interpretation in the American-English language. Inconsistencies with verb tense were identified, and it was decided to consistently use simple past tense. The wording of five items was modified to better suit the American-English language. In general, participants were positive on the comprehensibility, applicability and completeness of the questionnaire during the pilot-testing phase. Furthermore, the study showed positive results concerning the internal consistency (Cronbach's alphas for the scales between 0.79-0.89) and content validity of the American-English IWPQ. CONCLUSION: The results indicate that the cross-cultural adaptation of the American-English IWPQ was successful and that the measurement properties of the translated version are promising.

Improving the Individual Work Performance Questionnaire using Rasch analysis.

Recently, the Individual Work Performance Questionnaire (IWPQ) version 0.2 was developed using Rasch analysis. The goal of the current study was to improve targeting of the IWPQ scales by including additional items. The IWPQ 0.2 (original) and 0.3 (including additional items) were examined using Rasch analysis. Additional items that showed misfit or did not improve targeting were removed from the IWPQ 0.3, resulting in a final IWPQ 1.0. Subsequently, the scales showed good model fit and reliability, and were examined for key measurement requirements (e.g., category ordening, unidimensionality, and differential item functioning). Finally, calculation and interpretability of scores were addressed. Compared to its previous version, the final IWPQ 1.0 showed improved targeting for two out of three scales. As a result, it can more reliably measure workers at all levels of ability, discriminate between workers at a wider range on each scale, and detect changes in individual work performance.

Responsiveness of the individual work performance questionnaire.

BACKGROUND: Individual work performance is an important outcome measure in studies in the workplace. Nevertheless, its conceptualization and measurement has proven challenging. To overcome limitations of existing scales, the Individual Work Performance Questionnaire (IWPQ) was recently developed. The aim of the current study was to gain insight into the responsiveness of the IWPQ. METHODS: Data were used from the Be Active & Relax randomized controlled trial. The aim of the trial was to investigate the effectiveness of an intervention to stimulate physical activity and relaxation of office workers, on need for recovery. Individual work performance was a secondary outcome measure of the trial. In total, 39 hypotheses were formulated concerning correlations between changes on the IWPQ scales and changes on similar constructs (e.g., presenteeism) and distinct constructs (e.g., need for recovery) used in the trial. RESULTS: 260 Participants completed the IWPQ at both baseline and 12 months of follow-up. For the IWPQ scales, 23%, 15%, and 38%, respectively, of the hypotheses could be confirmed. In general, the correlations between change scores were weaker than expected. Nevertheless, at least 85% of the correlations were in the expected direction. CONCLUSIONS: Based on results of the current study, no firm conclusions can be drawn about the responsiveness of the IWPQ. Several reasons may account for the weaker than expected correlations. Future research on the IWPQ's responsiveness should be conducted, preferably in other populations and intervention studies, where greater changes over time can be expected.

Construct validity of the individual work performance questionnaire.

OBJECTIVE: To examine the construct validity of the Individual Work Performance Questionnaire (IWPQ). METHODS: A total of 1424 Dutch workers from three occupational sectors (blue, pink, and white collar) participated in the study. First, IWPQ scores were correlated with related constructs (convergent validity). Second, differences between known groups were tested (discriminative validity). RESULTS: First, IWPQ scores correlated weakly to moderately with absolute and relative presenteeism, and work engagement. Second, significant differences in IWPQ scores were observed for workers differing in job satisfaction, and workers differing in health. CONCLUSION: Overall, the results indicate acceptable construct validity of the IWPQ. Researchers are provided with a reliable and valid instrument to measure individual work performance comprehensively and generically, among workers from different occupational sectors, with and without health problems.

Measuring individual work performance: identifying and selecting indicators.

BACKGROUND: Theoretically, individual work performance (IWP) can be divided into four dimensions: task performance, contextual performance, adaptive performance, and counterproductive work behavior. However, there is no consensus on the indicators used to measure these dimensions. OBJECTIVE: This study was designed to (1) identify indicators for each dimension, (2) select the most relevant indicators, and (3) determine the relative weight of each dimension in ratings of work performance. METHODS: IWP indicators were identified from multiple research disciplines, via literature, existing questionnaires, and expert interviews. Subsequently, experts selected the most relevant indicators per dimension and scored the relative weight of each dimension in ratings of IWP. RESULTS: In total, 128 unique indicators were identified. Twenty-three of these indicators were selected by experts as most relevant for measuring IWP. Task performance determined 36% of the work performance rating, while the other three dimensions respectively determined 22%, 20% and 21% of the rating. CONCLUSIONS: Notable consensus was found on relevant indicators of IWP, reducing the number from 128 to 23 relevant indicators. This provides an important step towards the development of a standardized, generic and short measurement instrument for assessing IWP.

Active gaming in Dutch adolescents: a descriptive study.

BACKGROUND: Adequate levels of physical activity are part of a healthy lifestyle and in this way linked to better health outcomes. For children and adolescents, the physical activity guideline recommends at least 60 minutes of moderate-to-vigorous physical activity every day. However, many adolescents are not physically active enough and they spend a lot of their time on sedentary activities (such as video games). A new generation of video games that require body movements to play them, so-called "active games", could serve to increase physical activity in adolescents. The activity level while playing these games is comparable to light-to-moderate intensity physical activity. The current study aims to increase our understanding of 1) the demographic characteristics of adolescents who play active games regularly (≥ 1 hour per week) and non-regularly (< 1 hour per week), 2) time spent on active games, 3) the contribution of active games to daily physical activity and 4) the type and amount of activities being replaced by active gaming. METHODS: A cross-sectional survey was conducted in a Dutch internet panel, questioning adolescents in conjunction with one of their parents. A random sample of 320 households (with stratification on gender of the parent and the adolescent, the age of the adolescent and the region of the household) was selected that owned a console or application for active video games and that had a child aged 12 through 16 years. 201 child-parent couples (63% response) completed an internet survey with questions about demographics, physical activity and sedentary behaviour, and gaming behaviour. The questionnaire also contained questions designed to assess whether and how active gaming replaces other activities. Besides descriptive analyses, independent t-test, Pearson's chi-square and Mann-Whitney test (when data were not normally distributed) were used for comparisons between regular and non-regular active gamers. RESULTS: Eleven percent of the adolescents with an active game in their household never used the game. There were no significant differences in gender, education level (of adolescent and parent), ethnicity and sedentary behaviour between regular (n = 65) and non-regular active gamers (n = 114). Adolescents' (regular and non-regular active gamers) meantime spent on active gaming was 80 (± 136) minutes a week; this potentially amounts to 11% of total physical activity. When time spent on active gaming was included in the calculation of the percentage of adolescents that met the physical activity guideline, the percentage increased significantly (p < 0.05) from 67 to 73%. According to the adolescents, active gaming mainly replaces sedentary screen time such as TV viewing, internet and non-active gaming. Parental opinions concurred with this appraisal. CONCLUSIONS: The results of this study confirm the idea that active gaming may contribute to an active lifestyle in adolescents, primarily because it potentially contributes substantially to time spent on physical activity. Secondly, active gamers indicate that they spent time on active games which they would have spent otherwise on less active activities.

Conceptual frameworks of individual work performance: a systematic review.

OBJECTIVE: Individual work performance is differently conceptualized and operationalized in different disciplines. The aim of the current review was twofold: (1) identifying conceptual frameworks of individual work performance and (2) integrating these to reach a heuristic conceptual framework. METHODS: A systematic review was conducted in medical, psychological, and management databases. Studies were selected independently by two researchers and included when they presented a conceptual framework of individual work performance. RESULTS: A total of 17 generic frameworks (applying across occupations) and 18 job-specific frameworks (applying to specific occupations) were identified. Dimensions frequently used to describe individual work performance were task performance, contextual performance, counterproductive work behavior, and adaptive performance. CONCLUSION: On the basis of the literature, a heuristic conceptual framework of individual work performance was proposed. This framework can serve as a theoretical basis for future research and practice.

The cost-effectiveness of a lifestyle physical activity intervention in addition to a work style intervention on recovery from neck and upper limb symptoms and pain reduction in computer workers.

OBJECTIVES: To evaluate the cost-effectiveness of a work style (WS) intervention and a work style plus physical activity (WSPA) intervention in computer workers with neck and upper limb symptoms compared with usual care. METHODS: An economic evaluation was conducted from an employer's perspective and alongside a randomised controlled trial in which 466 computer workers with neck and upper limb symptoms were randomised to a WS group (N = 152), a WSPA group (N = 156) or a usual care group (N=158). Total costs were compared to the effects on recovery and pain intensity. In the primary analyses, missing effect data were imputed using multiple imputation techniques. RESULTS: Total costs during the 12-month intervention and follow-up period were €1907 (WS), €2811 (WSPA) and €2310 (usual care). Differences between groups were not statistically significant. Neither intervention was more effective than usual care in improving overall recovery. The WS intervention was more effective than usual care in reducing current pain, average pain and worst pain in the past 4 weeks, but the WSPA intervention was not. The acceptability curve showed that when a company is willing to pay approximately €900 for a 1-point reduction in average pain (scale from 0 to 10), the probability of cost-effectiveness compared to usual care is 95%. Similar results were observed for current and worst pain. CONCLUSIONS: This study shows that the WS intervention was not cost-effective for improving recovery but was cost-effective for reducing pain intensity, although this reduction was not clinically significant. The WSPA intervention was not cost-effective compared with usual care. Trial registration number ISRCTN87019406.

Improving work style behavior in computer workers with neck and upper limb symptoms.

INTRODUCTION: The goal of this study was to assess the effectiveness of a group-based interactive work style intervention in improving work style behavior. METHODS: Computer workers with neck and upper limb symptoms were randomised into the work style group (WS, N = 152), the work style and physical activity group (WSPA, N = 156), or the usual care group (N = 158). Both intervention groups received the same work style intervention but the WSPA group also received a lifestyle physical activity intervention. Participants from the intervention groups attended six group meetings which focused on behavioral change with regard to body posture and workstation adjustment, breaks, and coping with high work demands in order to reduce work stress. Stage of change, breaks and exercise behavior, and stress outcomes were assessed by questionnaire at baseline (T0) and after 6 (T1) and 12 months (T2). Body posture and workstation adjustment were assessed by observation and by questionnaire at T0, T1, and T2. Multilevel analyses were used to study differences in work style behavior between study groups. RESULTS: The work style intervention was effective in improving stage of change with regard to body posture, workstation adjustment, and the use of sufficient breaks during computer work. These findings were confirmed by higher self-reported use of breaks and exercise reminder software and less working hours without breaks. However, self-reported changes in body posture and workstation adjustment were less consistent. The work style intervention was ineffective in changing stress outcomes. CONCLUSION: A group-based work style intervention seems to be effective in improving some elements of work style behavior. Future studies should investigate the effectiveness of work style interventions on all dimensions of the Feuerstein work style model.

The effectiveness of a work style intervention and a lifestyle physical activity intervention on the recovery from neck and upper limb symptoms in computer workers.

This study assessed the effectiveness of a single intervention targeting work style and a combined intervention targeting work style and physical activity on the recovery from neck and upper limb symptoms. Computer workers with frequent or long-term neck and upper limb symptoms were randomised into the work style group (WS, n=152), work style and physical activity group (WSPA, n=156), or usual care group (n=158). The WS and WSPA group attended six group meetings. All meetings focused on behavioural change with regard to body posture, workplace adjustment, breaks and coping with high work demands (WS and WSPA group) and physical activity (WSPA group). Pain, disability at work, days with symptoms and months without symptoms were measured at baseline and after 6 (T1) and 12 months (T2). Self-reported recovery was assessed at T1/T2. Both interventions were ineffective in improving recovery. The work style intervention but not the combined intervention was effective in reducing all pain measures. These effects were present in the neck/shoulder, not in the arm/wrist/hand. For the neck/shoulder, the work style intervention group also showed an increased recovery-rate. Total physical activity increased in all study groups but no differences between groups were observed. To conclude, a group-based work style intervention focused on behavioural change was effective in improving recovery from neck/shoulder symptoms and reducing pain on the long-term. The combined intervention was ineffective in increasing total physical activity. Therefore we cannot draw conclusions on the effect of increasing physical activity on the recovery from neck and upper limb symptoms.

Physical activity, cardiorespiratory fitness, and body mass index in relationship to work productivity and sickness absence in computer workers with preexisting neck and upper limb symptoms.

OBJECTIVE: The purpose of this study was to investigate associations among three modifiable risk factors (ie, physical activity, cardiorespiratory fitness, and body mass index), work productivity, and sickness absence in computer workers. METHODS: All participants were computer workers with neck and upper limb symptoms in the preceding 6 months, the last 2 weeks, or both. Productivity and sickness absence were assessed with the Health and Performance Questionnaire (HPQ). RESULTS: Physical activity and cardiorespiratory fitness were not associated with work productivity or sickness absence. Obese male workers reported lower absolute productivity than lean workers. Lean and overweight workers reported similar productivity levels. Body mass index was not associated with sickness absence. CONCLUSIONS: In a population of white-collar workers with neck and upper limb symptoms, obese male workers showed significantly lower productivity than did lean or overweight workers.

The (cost-)effectiveness of a lifestyle physical activity intervention in addition to a work style intervention on the recovery from neck and upper limb symptoms in computer workers.

BACKGROUND: Neck and upper limb symptoms are frequently reported by computer workers. Work style interventions are most commonly used to reduce work-related neck and upper limb symptoms but lifestyle physical activity interventions are becoming more popular to enhance workers health and reduce work-related symptoms. A combined approach targeting work style and lifestyle physical activity seems promising, but little is known on the effectiveness of such combined interventions. METHODS/DESIGN: The RSI@Work study is a randomised controlled trial that aims to assess the added value of a lifestyle physical activity intervention in addition to a work style intervention to reduce neck and upper limb symptoms in computer workers. Computer workers from seven Dutch companies with frequent or long-term neck and upper limb symptoms in the preceding six months and/or the last two weeks are randomised into three groups: (1) work style group, (2) work style and physical activity group, or (3) control group. The work style intervention consists of six group meetings in a six month period that take place at the workplace, during work time, and under the supervision of a specially trained counsellor. The goal of this intervention is to stimulate workplace adjustment and to improve body posture, the number and quality of breaks and coping behaviour with regard to high work demands. In the combined (work style and physical activity) intervention the additional goal is to increase moderate to heavy physical activity. The control group receives usual care. Primary outcome measures are degree of recovery, pain intensity, disability, number of days with neck and upper limb symptoms, and number of months without neck and upper limb symptoms. Outcome measures will be assessed at baseline and six and 12 months after randomisation. Cost-effectiveness of the group meetings will be assessed using an employer's perspective. DISCUSSION: This study will be one of the first to assess the added value of a lifestyle physical activity intervention in addition to a work style intervention in reducing neck and upper limb symptoms of computer workers. The results of the study are expected in 2007.

In a prospective study in young people, associations between changes in smoking behavior and risk factors for cardiovascular disease were complex.

OBJECTIVE: This study investigates how voluntary changes in tobacco consumption are related to changes in biological risk factors for cardiovascular disease in 21- to 36-year-old men and women. STUDY DESIGN AND SETTING: Data of the Amsterdam Growth and Health Longitudinal Study (AGAHLS) were used to study the association between voluntary changes in tobacco consumption and changes in biological risk factors for cardiovascular disease (CVD) during 4-6 years of follow-up in 165 men and 195 women aged 21-36 years. We used multiple linear regression analyses with corrections for age and changes in other lifestyles. RESULTS: In both sexes, we found trends for a reduction in blood pressure, high-density lipoprotein cholesterol (HDL-C), body weight, and waist-to-hip ratio (WHR) and a rise in the ratio between total serum cholesterol (TC) and HDL-C (TC/HDL-C) with increasing tobacco consumption. Opposite trends were found with reducing tobacco consumption. In women, body weight, WHR, and waist circumference reduced significantly and independently with increasing tobacco consumption and increased significantly with decreasing tobacco consumption. CONCLUSION: These results suggest that voluntary changes in tobacco consumption go together with both healthy and unhealthy changes in biological risk factors for CVD.

Comparison between self-report and a dipstick method (NicCheck 1) to assess nicotine intake.

The purpose of this study was to investigate the agreement between self-reported tobacco consumption and NicCheck 1 (Dynagen Inc. Cambridge, Mass., USA) regarding smoking status and nicotine intake in a population of smokers (20.8%) and non-smokers. NicCheck 1 is a dipstick that changes colour in the presence of urinary nicotine metabolites. Smoking was assessed by self-report and NicCheck 1 in 169 males and 191 females (mean age 36.0 SD 0.7). Self-report and NicCheck 1 agreed highly on smoking status, especially in moderate to heavy smokers. With regard to nicotine intake, there was a large overlap in self-reported tobacco consumption between NicCheck 1 levels, despite a relatively high correlation coefficient between self-report and NicCheck 1 in smokers (i.e. 0.74). No effect modification by gender or BMI was found. When both methods were validated against two blood lipid parameters, self-report seemed to do equally well as NicCheck 1 in assessing nicotine intake.

Smoking and quantitative ultrasound parameters in the calcaneus in 36-year-old men and women.

Little is known regarding the association between smoking and quantitative ultrasound (QUS) parameters. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) are believed to provide information on bone quality besides information on bone mineral density (BMD). The aim of this study was to investigate (1) current tobacco smoking; (2) lifetime tobacco smoking; and (3) years since smoking cessation, in relation to QUS and BMD parameters in 36-year-old men and women. Data came from the ninth measurement of the Amsterdam Growth and Health Longitudinal Study (AGAHLS), in which 165 men (36 smokers and 129 nonsmokers) and 178 women (33 smokers and 145 nonsmokers) participated, with an average age of 36 years (SD = 0.7). BUA (dB/MHz) and SOS (m/s) of the calcaneus were assessed by using the CUBA Clinical instrument. BMD of the lumbar spine (L1-L4), total hip, and total body were measured with dual-energy X-ray absorptiometry (DXA). We used multiple linear regression analyses with correction for body weight, physical activity, calcium intake, and alcohol consumption. We found no significant associations between smoking and any of the BMD parameters in 36-year-old men and women. However, both current and lifetime tobacco smoking were significantly and negatively associated with BUA in women but not in men. Lifetime tobacco smoking was significantly and negatively associated with SOS in both sexes. The latter association was independent of body weight, calcium intake, physical activity, and alcohol consumption in women, but not in men. Our results suggest that both current and lifetime tobacco smoking are associated with a deterioration in bone quality but not with a reduction in BMD. However, since BMD parameters and QUS parameters were not measured at the same sites, our results may also simply suggest that the calcaneus is affected by smoking at an earlier stage than the lumbar spine, hip, and total body.