Anthropology of Deep Brain Stimulation; the 30th Anniversary of STN DBS in 2023.

Background: The year 2023 marks the 30th anniversary of deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson's disease (PD). This procedure prompted a universal interest in DBS for various brain disorders and resulted in a unique expansion of clinical and scientific collaboration between many disciplines, with impact on many aspects of society. Objective: To study the anthropology of DBS, that is, its ethno-geographic origins, its evolution, its impact on clinicians and scientists, and its influence on society at large. Material and Methods: The authors scrutinized the geo-ethnic origins of the pioneers of modern DBS, and they evaluated, based on the literature and on a long-term praxis, the development of DBS and its impact on clinicians, on healthcare, and on society. Results: Scientists and clinicians from various geo-ethnic origins pioneered modern DBS, leading to worldwide spread of this procedure and to the establishment of large multidisciplinary teams in many centers. Neurologists became actively involved in surgery and took on new laborious tasks of programming ever more complicated DBS systems. Publications sky-rocketed and the global spread of DBS impacted positively on several aspects of society, including healthcare, awareness of neurological diseases, interdisciplinary relations, conferences, patient organizations, unemployment, industry, etc. Conclusions: STN DBS has boosted the field of deep brain electrotherapy for many neurological and psychiatric illnesses, and DBS has generated a global benefit on many aspects of society, well beyond its clinical benefits on symptoms of diseases. With the ever-increasing indications for DBS, more positive global impact is expected.

10 Years Follow-Up of Deep Brain Stimulation in the Caudal Zona Incerta/Posterior Subthalamic Area for Essential Tremor.

Background: Long-term data on the effects of deep brain stimulation (DBS) for essential tremor (ET) is scarce, especially regarding DBS in the caudal Zona incerta (cZi) and the posterior subthalamic area (PSA). Objectives: The aim of this prospective study was to evaluate the effect of cZi/PSA DBS in ET at 10 years after surgery. Methods: Thirty-four patients were included. All patients received cZi/PSA DBS (5 bilateral/29 unilateral) and were evaluated at regular intervals using the essential tremor rating scale (ETRS). Results: One year after surgery, there was a 66.4% improvement of total ETRS and 70.7% improvement of tremor (items 1-9) compared with the preoperative baseline. Ten years after surgery, 14 patients had died and 3 were lost to follow-up. In the remaining 17 patients, a significant improvement was maintained (50.8% for total ETRS and 55.8% for tremor items). On the treated side the scores of hand function (items 11-14) had improved by 82.6% at 1 year after surgery, and by 66.1% after 10 years. Since off-stimulation scores did not differ between year 1 and 10, this 20% deterioration of on-DBS scores was interpreted as a habituation. There was no significant increase in stimulation parameters beyond the first year. Conclusions: This 10 year follow up study, found cZi/PSA DBS for ET to be a safe procedure with a mostly retained effect on tremor, compared to 1 year after surgery, and in the absence of increase in stimulation parameters. The modest deterioration of effect of DBS on tremor was interpreted as habituation.

Serendipity and Observations in Functional Neurosurgery: From James Parkinson's Stroke to Hamani's & Lozano's Flashbacks.

BACKGROUND: Serendipity and observations have a noble tradition in medicine, including neurology, and are responsible for many medical treatments (carbamazepine for tic douloureux, amantadine for Parkinson's disease, gabapentin for restless legs…). We aimed at examining the contribution of serendipity and observations to functional neurosurgery. Scholarly publications relevant to the history of functional neurosurgery for movement and psychiatric disorders were reviewed, starting from the pre-stereotactic era. The documents were scrutinized with respect to indications for surgery, surgical methods, and brain targets, in view of determining whether serendipitous discoveries and other observations contributed to various functional neurosurgical procedures. SUMMARY: James Parkinson's observation that tremors disappeared in the arm of a person with shaking palsy after a hemiparetic stroke encouraged neurosurgeons in the first half of the 20th century to perform ablative procedures on central motor pathways. Following a lobotomy performed by Browder that extended too far medially in a psychiatric patient with coexisting Parkinson's disease (PD), it was noted that the Parkinsonian signs improved. This encouraged Russel Meyers to carry out open surgery on the caudate nucleus and basal ganglia in PD. Cooper introduced ligation of the anterior choroidal artery as a treatment for PD following a surgical accident during a pedunculotomy. Cooper later started to perform stereotactic surgery on the ventrolateral thalamus following the pathological finding that an intended pallidal lesion had in fact targeted the thalamus. Leksell discovered the ideal location of a pallidal lesion being in the posteroventral area empirically, long before the advent of the basal ganglia model of PD. Modern Deep Brain Stimulation (DBS) that started in the thalamus for tremor was the result of an observation by Benabid that intraoperative high-frequency stimulation during a thalamotomy reduced tremor. Both the discoveries of the anterior limbic subthalamic nucleus as a DBS target for OCD and the medial forebrain bundle as a DBS target for depression occurred by chance. Hamani and Lozano observed memory flashbacks in a patient who was undergoing DBS for obesity, which led to the discovery of the fornix as a potential DBS target for Alzheimer's disease. KEY MESSAGES: In the history of functional neurosurgery, serendipity and observations have resulted in discoveries of several procedures, brain targets for lesioning or DBS as well as new clinical surgical indications. In this era of neuromodulation, this technology should be exquisite in allowing potential serendipitous discoveries, provided that clinicians remain both observant and prepared.

Flawed conclusions on the Västerbotten Intervention Program by San Sebastian et .al.

An evaluation of Västerbotten Intervention Programme (VIP) was recently conducted by San Sebastian et al. (BMC Public Health 19:202, 2019). Evaluation of health care interventions of this kind require 1) an understanding of both the design and the nature of the intervention, 2) correct definition of the target population, and 3) careful choice of the appropriate evaluation method. In this correspondence, we review the approach used by San Sebastian et al. as relates to these three criteria. Within this framework, we suggest important explanations for why the conclusions drawn by these authors contradict a large body of research on the effectiveness of the VIP.

Strengthening capacity to research the social determinants of health in low- and middle-income countries: lessons from the INTREC programme.

BACKGROUND: The INDEPTH Training & Research Centres of Excellence (INTREC) collaboration developed a training programme to strengthen social determinants of health (SDH) research in low- and middle-income countries (LMICs). It was piloted among health- and demographic researchers from 9 countries in Africa and Asia. The programme followed a blended learning approach and was split into three consecutive teaching blocks over a 12-month period: 1) an online course of 7 video lectures and assignments on the theory of SDH research; 2) a 2-week qualitative and quantitative methods workshop; and 3) a 1-week data analysis workshop. This report aims to summarise the student evaluations of the pilot and to suggest key lessons for future approaches to strengthen SDH research capacity in LMICs. METHODS: Semi-structured interviews and questionnaires with 24 students from 9 countries in Africa and Asia were used to evaluate each teaching block. Information was collected about the students' motivation and interest in studying SDH, any challenges they faced during the consecutive teaching blocks, and suggestions they had for future courses on SDH. RESULTS: Of the 24 students who began the programme, 13 (54%) completed all training activities. The students recognised the need for such a course and its potential to improve their skills as health researchers. The main challenges with the online course were time management, prior knowledge and skills required to participate in the course, and the need to get feedback from teaching staff throughout the learning process. All students found the face-to-face workshops to be of high quality and value for their work, because they offered an opportunity to clarify SDH concepts taught during the online course and to gain practical research skills. After the final teaching block, students felt they had improved their data analysis skills and were better able to develop research proposals, scientific manuscripts, and policy briefs. CONCLUSIONS: The INTREC programme has trained a promising cadre of health researchers who live and work in LMICs, which is an essential component of efforts to identify and reduce national and local level health inequities. Time management and technological issues were the greatest challenges, which can inform future attempts to strengthen research capacity on SDH.

Assessing dental professionals' understanding of tobacco prevention and control: a qualitative study in Västerbotten County, Sweden.

AIM: To assess dental professionals' understanding of tobacco prevention and control. MATERIALS AND METHODS: In Sweden dental hygienists receive training in tobacco prevention and control. The study setting is Västerbotton County in the north of Sweden where a number of successful tobacco control initiatives have been established. A purposeful sample comprising five male and four female dental professionals and trainees was selected. Data were collected through in-depth semi-structured individual interviews and analysed using content analysis. RESULTS: Informants acknowledged limited adherence to tobacco prevention. They were not confident of their knowledge of tobacco and non-communicable disease prevention and had limited awareness of global oral health policies. Reasons for poor adherence included professional fragmentation, lack of training, and the absence of reimbursement for time spent on prevention activities. DISCUSSION: The success of efforts to reduce smoking in Västerbotton County is attributed to the network of local public health initiatives with very limited involvement by local dental professionals. CONCLUSIONS: The findings highlight the need to more actively engage the dental workforce in tobacco control and prevention. Moreover, it is important to recognise that dental professionals can be public health advocates for tobacco control and prevention at global, national and local levels.

Impact of a combined community and primary care prevention strategy on all-cause and cardiovascular mortality: a cohort analysis based on 1 million person-years of follow-up in Västerbotten County, Sweden, during 1990-2006.

OBJECTIVE: To evaluate the impact of the Västerbotten Intervention Programme (VIP) by comparing all eligible individuals (target group impact) according to the intention-to-treat principle and VIP participants with the general Swedish population. DESIGN: Dynamic cohort study. SETTING/PARTICIPANTS: All individuals aged 40, 50 or 60 years, residing in Västerbotten County, Sweden, between 1990 and 2006 (N=101,918) were followed from their first opportunity to participate in the VIP until age 75, study end point or prior death. INTERVENTION: The VIP is a systematic, long-term, county-wide cardiovascular disease (CVD) intervention that is performed within the primary healthcare setting and combines individual and population approaches. The core component is a health dialogue based on a physical examination and a comprehensive questionnaire at the ages of 40, 50 and 60 years. PRIMARY OUTCOMES: All-cause and CVD mortality. RESULTS: For the target group, there were 5646 deaths observed over 1,054,607 person-years. Compared to Sweden at large, the standardised all-cause mortality ratio was 90.6% (95% CI 88.2% to 93.0%): for women 87.9% (95% CI 84.1% to 91.7%) and for men 92.2% (95% CI 89.2% to 95.3%). For CVD, the ratio was 95.0% (95% CI 90.7% to 99.4%): for women 90.4% (95% CI 82.6% to 98.7%) and for men 96.8% (95% CI 91.7 to 102.0). For participants, subject to further impact as well as selection, when compared to Sweden at large, the standardised all-cause mortality ratio was 66.3% (95% CI 63.7% to 69.0%), whereas the CVD ratio was 68.9% (95% CI 64.2% to 73.9%). For the target group as well as for the participants, standardised mortality ratios for all-cause mortality were reduced within all educational strata. CONCLUSIONS: The study suggests that the VIP model of CVD prevention is able to impact on all-cause and cardiovascular mortality when evaluated according to the intention-to-treat principle.

Training needs for research in health inequities among health and demographic researchers from eight African and Asian countries.

BACKGROUND: To support equity focussed public health policy in low and middle income countries, more evidence and analysis of the social determinants of health inequalities is needed. This requires specific know how among researchers. The INDEPTH Training and Research Centres of Excellence (INTREC) collaboration will develop and provide training on the social determinants of health approach for health researchers from the International Network for the Demographic Evaluation of Populations and Their Health in Low- and Middle-Income Countries (INDEPTH) in Africa and Asia. To identify learning needs among the potential target group, this qualitative study explored what INDEPTH researchers from Ghana, Tanzania, South Africa, Kenya, Indonesia, India, Vietnam, and Bangladesh feel that they want to learn to be able to conduct research on the causes of health inequalities in their country. METHODS: Using an inductive method, online concept-mapping, participants were asked to generate statements in response to the question what background knowledge they would need to conduct research on the causes of health inequalities in their country, to sort those statements into thematic groups, and to rate them in terms of how important it would be for the INTREC program to offer instruction on each of the statements. Statistical techniques were used to structure statements into a thematic cluster map and average importance ratings of statements/clusters were calculated. RESULTS: Of the 150 invited researchers, 82 participated in the study: 54 from Africa; 28 from Asia. Participants generated 59 statements and sorted them into 6 broader thematic clusters: "assessing health inequalities"; "research design and methods"; "research and policy"; "demography and health inequalities"; "social determinants of health" and "interventions". African participants assigned the highest importance to further training on methods for assessing health inequalities. Asian participants assigned the highest importance to training on research and policy. CONCLUSION: The identified thematic clusters and statements provide a detailed understanding of what INDEPTH researchers want to learn in order to be able to conduct research on the social determinants of health inequalities. This offers a framework for developing capacity building programs in this emerging field of public health research.

Association of climatic factors with infectious diseases in the Arctic and subarctic region--a systematic review.

BACKGROUND: The Arctic and subarctic area are likely to be highly affected by climate change, with possible impacts on human health due to effects on food security and infectious diseases. OBJECTIVES: To investigate the evidence for an association between climatic factors and infectious diseases, and to identify the most climate-sensitive diseases and vulnerable populations in the Arctic and subarctic region. METHODS: A systematic review was conducted. A search was made in PubMed, with the last update in May 2013. Inclusion criteria included human cases of infectious disease as outcome, climate or weather factor as exposure, and Arctic or subarctic areas as study origin. Narrative reviews, case reports, and projection studies were excluded. Abstracts and selected full texts were read and evaluated by two independent readers. A data collection sheet and an adjusted version of the SIGN methodology checklist were used to assess the quality grade of each article. RESULTS: In total, 1953 abstracts were initially found, of which finally 29 articles were included. Almost half of the studies were carried out in Canada (n=14), the rest from Sweden (n=6), Finland (n=4), Norway (n=2), Russia (n=2), and Alaska, US (n=1). Articles were analyzed by disease group: food- and waterborne diseases, vector-borne diseases, airborne viral- and airborne bacterial diseases. Strong evidence was found in our review for an association between climatic factors and food- and waterborne diseases. The scientific evidence for a link between climate and specific vector- and rodent-borne diseases was weak due to that only a few diseases being addressed in more than one publication, although several articles were of very high quality. Air temperature and humidity seem to be important climatic factors to investigate further for viral- and bacterial airborne diseases, but from our results no conclusion about a causal relationship could be drawn. CONCLUSIONS: More studies of high quality are needed to investigate the adverse health impacts of weather and climatic factors in the Arctic and subarctic region. No studies from Greenland or Iceland were found, and only a few from Siberia and Alaska. Disease and syndromic surveillance should be part of climate change adaptation measures in the Arctic and subarctic regions, with monitoring of extreme weather events known to pose a risk for certain infectious diseases implemented at the community level.

No association found between cardiovascular mortality, and job demands and decision latitude: experience from the Västerbotten Intervention Programme in Sweden.

The current prospective study with the longest follow-up period in Northern Sweden aims to investigate the association between job demands and decision latitude and cardiovascular disease (CVD) mortality. Further, we aim to assess the effect of conventional risk factors (i.e., body mass index, alcohol consumption, physical activity, marital status, education and smoking) on the association between job demands and decision latitude and CVD mortality. The data originated from the Linnaeus database, available at the Center for Population Studies, Umeå University, Sweden. A cohort of men and women aged 40, 50 and 60 years were recruited from the Västerbotten Intervention Programme. Deaths due to stroke and myocardial infarction at the end of the follow up are considered the outcome. Baseline job characteristics were defined by the Swedish version of the Karasek demand/control model. Statistical methods include proportional Cox hazard modeling and Relative Excess Risk due to Interaction (RERI) to assess interactions. The findings from this study did not support the association between job demands and decision latitude and CVD mortality. Instead, conventional risk factors were found stronger predictors, most evidently education differentials were associated with CVD mortality. We know from previous research that the greater the attenuation of the gradient after adjustment for a given risk factor, the greater the potential to reduce educational inequality via interventions that target this factor. Based on the present findings of the experience in Västerbotten, further research is needed to identify other risk factors besides job strain and its components that would reduce the socioeconomic gradient in CVD mortality.

Increasing the provision of mental health care for vulnerable, disaster-affected people in Bangladesh.

BACKGROUND: Bangladesh has the highest natural disaster mortality rate in the world, with over half a million people lost to disaster events since 1970. Most of these people have died during floods or cyclones, both of which are likely to become more frequent due to global climate change. To date, the government's post-disaster response strategy has focused, increasingly effectively, on the physical needs of survivors, through the provision of shelter, food and medical care. However, the serious and widespread mental health consequences of natural disasters in Bangladesh have not yet received the attention that they deserve. This Debate article proposes a practical model that will facilitate the provision of comprehensive and effective post-disaster mental health services for vulnerable Bangladeshis on a sustainable basis. DISCUSSION: A series of socially determined factors render the women and the poor of Bangladesh particularly vulnerable to dying in natural disasters; and, for those who survive, to suffering from some sort of disaster-related mental health illness. For women, this is largely due to the enforced gender separation, or purdah, that they endure; while for the poor, it is the fact that they are, by definition, only able to afford to live in the most climatically dangerous, and under-served parts of the country. Although the disasters themselves are brought by nature, therefore, social determinants increase the vulnerability of particular groups to mental illness as a result of them. While deeply entrenched, these determinants are at least partially amenable to change through policy and action. SUMMARY: In response to the 2004 Indian Ocean tsunami, the World Health Organisation developed a framework for providing mental health and psychosocial support after major disasters, which, we argue, could be adapted to Bangladeshi post-cyclone and post-flood contexts. The framework is community-based, it includes both medical and non-clinical components, and it could be adapted so that women and the poor are actively sought out and provided for. After training, these services could be run by Bangladesh's pre-existing 50,000-strong Cyclone Preparedness Programme workforce, alongside the country's extensive network of community-based health workers.

Evaluating reporting heterogeneity in self-rated health among adults aged 50 years and above in India: an anchoring vignettes analytic approach.

OBJECTIVE: To use anchoring vignettes to evaluate reporting heterogeneity (RH) in self-rated mobility and cognition in older adults. METHOD: We analyzed vignettes and self-rated mobility and cognition in 2,558 individuals aged 50 years and above. We tested for assumptions of vignette equivalence (VE) and response consistency (RC). We used a joint hierarchical ordered probit (HOPIT) model to evaluate self-rating responses for RH. RESULTS: The assumption of VE was met except for "learning" vignettes. Higher socioeconomic status (SES) and education significantly lowered thresholds for cognition ratings. After correction for RH, women, lower SES, and older respondents were significantly more likely to report greater difficulty in mobility. The influence of age, SES, and education on thresholds was less apparent for cognition. DISCUSSION: Our study provides strong evidence of RH in self-rated mobility and cognition. We highlight the need to formally test basic assumptions before using vignettes to adjust self-rating responses for RH.

Self-rated health: small area large area comparisons amongst older adults at the state, district and sub-district level in India.

We compared prevalence estimates of self-rated health (SRH) derived indirectly using four different small area estimation methods for the Vadu (small) area from the national Study on Global AGEing (SAGE) survey with estimates derived directly from the Vadu SAGE survey. The indirect synthetic estimate for Vadu was 24% whereas the model based estimates were 45.6% and 45.7% with smaller prediction errors and comparable to the direct survey estimate of 50%. The model based techniques were better suited to estimate the prevalence of SRH than the indirect synthetic method. We conclude that a simplified mixed effects regression model can produce valid small area estimates of SRH.

Use of anchoring vignettes to evaluate health reporting behavior amongst adults aged 50 years and above in Africa and Asia--testing assumptions.

BACKGROUND: Comparing self-rating health responses across individuals and cultures is misleading due to different reporting behaviors. Anchoring vignettes is a technique that allows identifying and adjusting self-rating responses for reporting heterogeneity (RH). OBJECTIVE: This article aims to test two crucial assumptions of vignette equivalence (VE) and response consistency (RC) that are required to be met before vignettes can be used to adjust self-rating responses for RH. DESIGN: We used self-ratings, vignettes, and objective measures covering domains of mobility and cognition from the WHO study on global AGEing and adult health, administered to older adults aged 50 years and above from eight low- and middle-income countries in Africa and Asia. For VE, we specified a hierarchical ordered probit (HOPIT) model to test for equality of perceived vignette locations. For RC, we tested for equality of thresholds that are used to rate vignettes with thresholds derived from objective measures and used to rate their own health function. RESULTS: There was evidence of RH in self-rating responses for difficulty in mobility and cognition. Assumptions of VE and RC between countries were violated driven by age, sex, and education. However, within a country context, assumption of VE was met in some countries (mainly in Africa, except Tanzania) and violated in others (mainly in Asia, except India). CONCLUSION: We conclude that violation of assumptions of RC and VE precluded the use of anchoring vignettes to adjust self-rated responses for RH across countries in Asia and Africa.

Life course socioeconomic position and mortality: a population register-based study from Sweden.

AIMS: Adverse social circumstances during one's life course have been related to an increased risk of mortality. This article extends the literature by focusing on adversity at each phase of, and cumulatively at midlife in the Swedish population. METHODS: Data on socioeconomic indicators from 1970, 1980 and 1990 were linked to death registrations from 2000 to 2009. Relative indices of inequalities were computed for socioeconomic indicators, in order to measure the cumulative impact of inequality on mortality. RESULTS: A significant cumulative effect of being in the worst-off socioeconomic groups was found. For men, almost all indicators had a significant independent impact on risk of death. Among women, significant independent impacts were found for education in 1990 and for socioeconomic index in the 2 census years of 1970 and 1980. CONCLUSIONS: Being disadvantaged during a longer period in midlife has a significant negative impact on health. Policies targeted to reduce health inequality should focus on every stage of the midlife course.

Addressing research capacity for health equity and the social determinants of health in three African countries: the INTREC programme.

BACKGROUND: The importance of tackling economic, social and health-related inequities is increasingly accepted as a core concern for the post-Millennium Development Goal framework. However, there is a global dearth of high-quality, policy-relevant and actionable data on inequities within populations, which means that development solutions seldom focus on the people who need them most. INTREC (INDEPTH Training and Research Centres of Excellence) was established with this concern in mind. It aims to provide training for researchers from the INDEPTH network on associations between health inequities, the social determinants of health (SDH), and health outcomes, and on presenting their findings in a usable form to policy makers. OBJECTIVE: As part of a baseline situation analysis for INTREC, this paper assesses the current status of SDH training in three of the African INTREC countries - Ghana, Tanzania, and South Africa - as well as the gaps, barriers, and opportunities for training. METHODS: SDH-related courses from the three countries were identified through personal knowledge of the researchers, supplemented by snowballing and online searches. Interviews were also conducted with, among others, academics engaged in SDH and public health training in order to provide context and complementary material. Information regarding access to the Internet, as a possible INTREC teaching medium, was gathered in each country through online searches. RESULTS: SDH-relevant training is available, but 1) the number of places available for students is limited; 2) the training tends to be public-health-oriented rather than inclusive of the broader, multi-sectoral issues associated with SDH; and 3) insufficient funding places limitations on both students and on the training institutions themselves, thereby affecting participation and quality. We also identified rapidly expanding Internet connectivity in all three countries, which opens up opportunities for e-learning on SDH, though the current quality of the Internet services remains mixed. CONCLUSIONS: SDH training is currently in short supply, and there is a clear role for INTREC to contribute to the training of a critical mass of African researchers on the topic. This work will be accomplished most effectively by building on pre-existing networks, institutions, and methods.

Does self-rated health predict death in adults aged 50 years and above in India? Evidence from a rural population under health and demographic surveillance.

BACKGROUND: The Study on Global Ageing and Adult Health (SAGE) aims to improve empirical understanding of health and well-being of adults in developing countries. We examine the role of self-rated health (SRH) in predicting mortality and assess how socio-demographic and other disability measures influence this association. METHODS: In 2007, a shortened SAGE questionnaire was administered to 5087 adults aged ≥50 years under the Health Demographic Surveillance System in rural Pune district, India. Respondents rated their own health with a single global question on SRH. Disability and well-being were assessed using the WHO Disability Assessment Schedule Index, Health State Score and quality-of-life score. Respondents were followed up every 6 months till June 2011. Any change in spousal support, migration or death during follow-up was updated in the SAGE dataset. RESULTS: In all, 410 respondents (8%) died in the 3-year follow-up period. Mortality risk was higher with bad/very bad SRH [hazard ratio (HR) in men: 3.06, 95% confidence interval (CI): 1.93-4.87; HR in women: 1.64, 95% CI: 0.94-2.86], independent of age, disability and other covariates. Disability measure (WHO Disability Assessment Schedule Index) and absence of spousal support were also associated with increased mortality risk. CONCLUSION: Our findings confirm an association between bad/very bad SRH and mortality for men, independent of age, socio-demographic factors and other disability measures, in a rural Indian population. This association loses significance in women when adjusted for disability. Our study highlights the strength of nesting cross-sectional surveys within the context of the Health Demographic Surveillance System in studying the role of SRH and mortality.