Alternative green solvents associated with ultrasound-assisted extraction: A green chemistry approach for the extraction of carotenoids and chlorophylls from microalgae.

This study proposes a method for the ultrasonic extraction of carotenoids and chlorophyll from Scenedesmus obliquus and Arthrospira platensis microalgae with green solvents. Ethanol and ethanolic solutions of ionic liquids were tested with a variety of extraction parameters, including number of extractions, time of extraction, and solid-liquid ratio R(S/L), to determine the optimal conditions. After selecting the most effective green solvent (ethanol), the process conditions were established: R(S/L) of 1:10, three extraction cycles at 3 min each), giving an extraction yield of 2602.36 and 764.21 µgcarotenoids.gdried biomass-1; and 22.01 and 5.81 mgchlorophyll.gdried biomass-1 in S. obliquus and A. platensis, respectively. The carotenoid and chlorophyll extracts obtained using ethanol were shown to be potent scavengers of peroxyl radical, being 5.94 to 26.08 times more potent α-tocopherol. These findings pave the way for a green strategy for valorizing microalgal biocompounds through efficient and environmentally friendly technological processes.

Guidance for formulating ingredients/products from Chlorella vulgaris and Arthrospira platensis considering carotenoid and chlorophyll bioaccessibility and cellular uptake.

This study aimed to investigate the impact of different microalgal matrices on the bioaccessibility and uptake by Caco-2 cells of carotenoids and chlorophylls. In this way, the microalgal ingredients/products (whole dry biomass [WDB], whole ultrasonicated paste [WUP], and liposoluble pigment emulsion [LPE]) obtained from Chlorella vulgaris and Arthrospira platensis were submitted to in vitro simulated digestion. Apical uptake of pigments in micelles generated during the simulated digestion by Caco-2 human intestinal cells was determined. The influence of simulated digestion on carotenoid and chlorophyll stability and bioaccessibility was assessed by HPLC-PDA-MS/MS and the carotenoids and chlorophylls' bioaccessibility and cellular uptake were shown to be boosted according to the matrix (LPE > WUP > WDB). Our findings showed that Chlorella vulgaris and Arthrospira platensis could be considered in formulations when carotenoids and chlorophylls are the target molecules in the ingredients/products.

Insights on the Bioaccessibility of Natural Pigments from Diatom Chaetoceros calcitrans.

This study aimed to investigate the bioaccessibility of carotenoids and chlorophylls from the biomass of microalgae Chaetoceros calcitrans. The samples were submitted to an in vitro digestion protocol, and the compounds were determined by HPLC-PDA-MS/MS. A total of 13 compounds were identified in all tests. After in vitro digestion, the relative bioaccessibility of carotenoids and chlorophylls ranged from 4 to 58%. The qualitative profile of carotenoids reflected the initial sample, with all-E-zeaxanthin (57.2%) being the most bioaccessible compound, followed by all-E-neochrome (31.26%), the latter being reported for the first time in the micellar fraction. On the other hand, among the chlorophylls only pheophytin a (15.01%) was bioaccessible. Furthermore, a chlorophyll derivative (Hydroxypheophytin a') was formed after in vitro digestion. Considering all compounds, xanthophylls (12.03%) and chlorophylls (12.22%) were significantly (p < 0.05) more bioaccessible than carotenes (11.22%). Finally, the considerable individual bioaccessibilities found, especially for zeaxanthin, demonstrate the bioactive potential of this bioresource. However, the large reduction in the totality of compounds after in vitro digestion suggests that additional technological strategies should be explored in the future to increase the efficiency of micellarization and enhance its bioactive effects.

Closing the gap in postfracture care at the population level: a randomized controlled trial.

BACKGROUND: Postfracture care is suboptimal, and strategies to address this major gap in care are necessary. We investigated whether notifications sent by mail to physicians and patients would lead to improved postfracture care. METHODS: We conducted a randomized controlled trial (ClinicalTrials.gov identifier NCT00594789) in the province of Manitoba, Canada, from June 2008 to May 2010. Using medical claims data, we identified 4264 men and women age 50 years or older who recently reported major fractures, and who had not undergone recent bone mineral density testing or treatment for osteoporosis. Participants were randomized to three groups: group 1 received usual care (n = 1480), patients in group 2 had mailed notification of the fracture sent to their primary care physicians (n = 1363), and group 3 had notifications sent to both physicians and patients (n = 1421). Bone mineral density testing and the start of pharmacologic treatment for osteoporosis within the following 12 months were documented. RESULTS: Among participants in group 1 (usual care), 15.8% of women and 7.6% of men underwent testing for bone mineral density or started pharmacologic treatment for osteoporosis. Outcome measures improved among participants in group 2 (30.3% of women and 19.0% of men, both p < 0.001) and group 3 (34.0% of women and 19.8% of men, both p < 0.001). No additional benefit was seen with patient notification in addition to physician notification. Combining groups 2 and 3, the absolute increase for the combined end point of bone mineral density testing or pharmacologic treatment was 14.9% (16.4% among women, 11.8% among men). The number needed to notify to change patient care was 7 (6 for women, 6 for men). The adjusted odds ratio (OR) to change patient care in group 2 was 2.45 (95% confidence interval [CI] 2.01-2.98); for group 3 the OR was 2.82 (95% CI 2.33-3.43). INTERPRETATION: This notification system provides a relatively simple way to enhance post-fracture care.

Closing the postfracture care gap using administrative health databases: design and implementation of a randomized controlled trial.

Postfracture care is suboptimal, and strategies to address this major care gap are urgently required. Case management is effective but is resource intensive and difficult to deliver to a widely scattered population. We describe the design and successful implementation of a randomized controlled trial (NCT00594789), which uses provincial administrative health databases to notify eligible physicians and patients after a major osteoporotic fracture that such fractures warrant additional assessment or pharmacologic treatment to prevent subsequent fractures. Men and women aged 50 yr or older residing in the Province of Manitoba, Canada, with a recently reported clinical fracture (hip, spine, humerus, and forearm) from medical claims data, and without recent bone mineral density (BMD) testing (in the last 3 yr) or osteoporosis therapy (in the last year), were randomized to 3 groups: group 1 received usual care, group 2 (physicians only) had mailed notification to the primary care physicians (alert letter, BMD requisition, and management flowchart), and group 3 (physicians and patient) had both physician notifications and patient notification (alert letter). During the initial 10 mo (from June 2008 to March 2009), 2901 fracture patients meeting the inclusion criteria were randomized. Groups were well balanced. Direct costs related to the initiative (programming, case identification, and mailings) were Canadian dollars (CAD$)12,379 during the pilot phase, which translates to CAD$6.50 per notification (groups 2 and 3). Ongoing costs (which exclude the initial programming costs) are estimated at CAD$1.25 per notification. This postfracture intervention, based on medical claims data, provides an easy way to enhance postfracture care. The approach is scalable, can be delivered to a widely scattered population, and requires minimal infrastructure. This low-cost intervention may complement more resource-intensive programs based on case managers.

Single-site vs multisite bone density measurement for fracture prediction.

BACKGROUND: Bone density measurement with dual-energy x-ray absorptiometry is widely used for fracture risk assessment. Discordance between measurement sites is common, but it is unclear how this affects fracture prediction. METHODS: We performed a historical cohort study among 16 505 women 50 years or older at the time of baseline dual-energy x-ray absorptiometry of the spine and hip (mean +/- SD observation period, 3.2 +/- 1.5 years). The study population was drawn from a database that contains all clinical dual-energy x-ray absorptiometry test results for the province of Manitoba, Canada. Each subject's longitudinal health service record was assessed for the presence of fracture codes after bone density testing. The likelihood ratio test was used to assess the improvement in fracture prediction from Cox proportional hazards models using bone density covariates from a single site or from combined sites. RESULTS: Age-adjusted hazard ratios (HRs) per standard deviation for osteoporotic fracture ranged from 1.61 (95% confidence interval [CI], 1.39-1.87) for the lumbar spine to 1.85 (95% CI, 1.70-2.01) for the total hip, with intermediate values for the femur neck (HR, 1.76 [95% CI, 1.62-1.92]) and trochanter (HR, 1.77 [95% CI, 1.63-1.92]). For fracture prediction, use of the minimum bone density measurement was no better than use of a hip measurement alone. When the total hip measurement was included in a fracture prediction model for the overall population, none of the other measurements added substantial information. The spine was the most useful site for the prediction of spine fractures alone. CONCLUSIONS: Proximal femur bone density measurements consistently outperformed lumbar spine measurements for global fracture prediction. In this cohort, the total hip was the best site for overall fracture assessment.

Antidepressant utilization in British Columbia from 1996 to 2004: increasing prevalence but not incidence.

OBJECTIVES: Expenditures on antidepressants in Canada are rapidly increasing; yet few studies have analyzed the characteristics of antidepressant users. This study investigated the prevalence and incidence of antidepressant use in British Columbia over eight years. METHODS: Antidepressant utilization and demographic data were assessed for the population of British Columbia from 1996 to 2004. Prescription claims were identified within the PharmaNet database for serotonin reuptake inhibitors (SSRI), tricyclics, monoamine oxidase inhibitors, bupropion (categorized separately for smoking cessation), and "novel" antidepressants, such as venlafaxine. Incident utilization (dispensed "first" antidepressant after two years without an antidepressant claim) and prevalent utilization were analyzed. All cohort members were required to have continuous registration with British Columbia medical services for at least two years before the first antidepressant claim. RESULTS: Prevalence of antidepressant use doubled, from 34 to 72 users per 1,000 population, between 1996 and 2004. The prevalence of particular classes of antidepressants also changed over time. Prevalence of novel antidepressants and SSRIs increased, although incidence of SSRIs decreased. Prevalent and incident use of bupropion for smoking cessation peaked in 1999 but then declined. Quarterly incident antidepressant use increased in 1998 and 1999 (6.5 and 11.3 users per 1,000) but decreased through 2004 (4.2 users per 1,000). Those aged 20 to 44 years and those aged 45 to 64 years showed the greatest peak in incident antidepressant use. A socioeconomic gradient in prescribing was observed. CONCLUSIONS: Prevalent antidepressant use has increased dramatically since 1996. By contrast, incident use increased from 1998 to 1999 but then decreased through 2004. Many complex factors likely contribute to antidepressant prescribing patterns.

Number of osteoporotic sites and fracture risk assessment: a cohort study from the Manitoba Bone Density Program.

UNLABELLED: Site-discordance in BMD assessment is common and significantly affects patient categorization. Greater number of osteoporotic sites correlates with lower T scores at each index site. This largely explains the positive association between number of osteoporotic sites and fracture risk. INTRODUCTION: Site-discordance in BMD is common when used to classify patients based on a cut-off T score of -2.5. It is unclear whether fracture risk assessment is improved by considering BMD information from multiple sites. Our objective was to assess the contribution of number of osteoporotic sites to overall fracture risk. MATERIALS AND METHODS: The study population was drawn from the regionally based clinical database of the Manitoba Bone Density Program that includes all clinical DXA test results for the Province of Manitoba, Canada. Analyses were limited to 16,505 women>or=50 years of age at the time of baseline DXA of the spine (L1-L4) and hip (three sites). During follow-up (3.2+/-1.5 years), longitudinal health service records showed 765 women with at least one osteoporotic fracture code (hip, forearm, spine, or humerus). RESULTS: Of 5012 women classified as osteoporotic by at least one site (T score -2.5 or lower), almost one half (2370; 47%) were abnormal at only a single site. Among the 1856 women with an osteoporotic total hip measurement, mean total hip T scores decreased as the number of additional osteoporotic sites increased (-2.58, no other osteoporotic sites; -2.69, one other site; -2.87, two other sites; -3.17, three other sites; Spearman r=-0.44, p<0.0001). Age-adjusted fracture risk from a Cox proportional hazards model increased as the number of osteoporotic sites increased (p<0.0001), but number of osteoporotic sites was no longer an independent predictor after total hip BMD was included as a covariate (p=0.19). Covariate adjustment for other sites of BMD measurement attenuated, but did not eliminate, the effect of number of osteoporotic sites. CONCLUSIONS: Site-discordance is common and significantly affects patient categorization when different skeletal sites are used for diagnosis. Greater number of osteoporotic sites correlates with lower T scores at each index site. This largely explains the positive association between number of osteoporotic sites and fracture risk.

Effectiveness of bone density measurement for predicting osteoporotic fractures in clinical practice.

CONTEXT: Bone density measurement with dual-energy x-ray absorptiometry is widely used for fracture risk assessment. It has not been established that published gradients of fracture risk from study populations can be directly applied to clinical populations. OBJECTIVE: The objective of the study was to assess osteoporotic fracture prediction with dual-energy x-ray absorptiometry in a large clinical cohort. DESIGN: This was a historical cohort study (mean observation period 3.2 +/- 1.5 yr). PATIENTS: The study population was drawn from the population-based database of the Manitoba Bone Density Program. Analyses were limited to women aged 50 yr or older at baseline (n = 16,505). MAIN OUTCOME MEASURE: Each subject's longitudinal health service record was assessed for the presence of nontrauma fracture codes (hip, spine, wrist, and humerus) after bone density testing. Age-adjusted hazard ratios for fracture were derived from Cox proportional hazards models. RESULTS: Site-specific and overall fracture rates were significantly associated with each site of bone density measurement (all P < 0.00001). The 95% confidence intervals overlapped those from a widely cited metaanalysis of fracture prediction from different sites. Although fracture prediction was not significantly different between the three hip measurement sites, each hip site was better than the lumbar spine for predicting overall fractures (nonoverlapping 95% confidence intervals). The manufacturer sd (equivalent to a unit change in T-score) resulted in a significantly smaller gradient of risk for the spine than when the population sd was used. CONCLUSIONS: Bone density measurements are effective for predicting fractures in clinical practice. However, hip measurements were superior to the spine in overall osteoporotic fracture prediction.

Toward a standard definition and measurement of persistence with drug therapy: Examples from research on statin and antihypertensive utilization.

BACKGROUND: Long-term utilization of prescription drugs for chronic conditions such as hypertension and/or hypercholesterolemia is a reality for millions of individuals, yet therapies may be discontinued before they can exert their beneficial effect. Several studies have measured the mean duration of therapy (ie, persistence) using administrative health databases. However, the terminology and methodology used for measuring persistence varied across studies, making it difficult to compare persistence rates. OBJECTIVES: The objectives of this study were to identify currently used measures of persistence and to propose a standard operational definition for use in administrative database analyses of drug utilization. METHODS: MEDLINE was searched for English-language articles published between January 1997 and June 2005 that quantified the concepts of persistence, adherence, compliance, or continuity with statin or antihypertensive therapy using administrative prescription claims databases. The conceptual and operational definitions of persistence used in the identified studies were categorized and applied to prescription-refill data for a hypothetical patient to compare the durations of persistence resulting from each method. RESULTS: Thirty-one articles were identified and reviewed. Few of the studies explicitly stated the conceptual definition of persistence used. Five methods of measuring persistence were identified: anniversary models, minimum-refills models, refill-sequence models, proportion-of-days-covered models, and hybrid models. When these models were applied to data for the hypothetical patient, total persistence with drug therapy ranged from 7 days to >1 year. CONCLUSIONS: There continue to be inconsistencies in the definition of persistence and the methods by which it is measured. A standard operational definition of persistence should be 2-dimensional, quantifying not only the total duration of therapy, but also the intensity of medication-taking within this interval.

Income-based drug coverage in British Columbia: the impact on access to medicines.

BACKGROUND AND OBJECTIVES: In May 2003, the government of British Columbia adopted income-based pharmacare, replacing an age-based program. Stated policy goals included the maintenance or enhancement of access to necessary medicines. This study examines the policy impact on access to two widely used drugs for chronic risk factors (antihypertensives and statins). METHODS: Data on incident antihypertensive and statin prescriptions between 1997 and 2004 were extracted from PharmaNet. Incident antihypertensive users were those who filled a first prescription after residing in the province for at least two years prior to the initial prescription date. The number of patients who ceased to fill a contiguous series of prescriptions (within 120 days of one another) was used as a measure of apparent discontinuation or interruption of therapy. We used time series analysis to test for changes in incident use and discontinuation. RESULTS: Between 1997 and 2004, 530,167 BC residents initiated therapy with an antihypertensive, and 264,904 BC residents initiated therapy with a statin. The 2003 policy change had no statistically significant impact on incident use of antihypertensives or statins, when stratified by age or income. Similarly, the 2003 policy did not change the rate of apparent discontinuations of therapy across age and income groups. However, a co-payment introduced in 2002 did increase end-of-year seasonality in apparent discontinuations in seniors--a finding that deserves further research. DISCUSSION: The 2003 transition to income-based pharmacare in British Columbia did not result in significant changes in access to, or continuation of, prescriptions to treat two leading chronic risk factors.

Income-Based Drug Coverage in British Columbia: Lessons for BC and the Rest of Canada.

BACKGROUND: In May 2003, the government of British Columbia adopted income-based pharmacare, replacing an age-based drug benefits program. Stated policy goals included reducing government spending, maintaining or enhancing access to medicines and improving financial equity. The province's experience on these policy dimensions can inform policy making in other jurisdictions and offers insight into priorities for Canada's National Pharmaceuticals Strategy. METHOD: The research team created an anonymized database with information about drug use, private and public expenditure and household income for all residents of British Columbia from 1996 to 2004. This database was used to evaluate the impact of the policy on trends in drug expenditures, utilization and sources of payment for seniors and non-seniors of different income levels. RESULTS: In the immediate term, Fair PharmaCare appears to have met many of its policy goals. Government spending was reduced. Access to medicines was maintained (though not enhanced). And the distributions of private and public expenditures were brought more closely in line with distribution of income. Long-run impacts depend largely on how a reduced role for government affects trends in costs, access and equity. Early indications suggest that a larger role for government may be needed to maintain performance on desired policy objectives over time. CONCLUSION: In the long run, there is reason for setting a new national standard for pharmacare that increases, not decreases, the share of publicly covered spending in every province. The federal government could play a key role by helping provinces increase public funding for prescription drugs and thereby facilitate cost control, maintain access to medicines and enhance financial equity.

The impact of hip subregion reference data on osteoporosis diagnosis.

Manufacturers of bone densitometry devices have been moving from manufacturer-specific reference values to data derived from larger population-based cohorts such as the National Health and Nutrition Evaluation Survey (NHANES) III. One bone densitometer manufacturer has released software that provides hip subregion T-score calculations based upon four slightly different versions of hip reference data. Our aim was to determine how changes in hip reference data affect diagnostic classification based on minimum T-scores in older women. We extracted results for lumbar spine and hip bone density measurements from the Manitoba Bone Density database for women aged 50 years or older who had baseline scans on the manufacturer's equipment (n=17,053). T-scores were calculated using manufacturer-specific non-NHANES data and three software implementations of NHANES reference data. One software version gave results at subregions of the hip that were significantly lower than with the three other sets of reference data from the same manufacturer (mean femoral neck T-score absolute difference 0.23-0.48, P<0.00001; mean trochanter T-score absolute difference 0.49-0.70, P<0.00001). As a result the proportion of measurements with a T-score of -2.5 or lower almost doubled at the femoral neck (14.3 versus 27.7%, P<0.00001) and approximately tripled at the trochanter (8.1 versus 24.0%, P<0.00001). The final patient classification of osteoporosis based on a minimum T-score of -2.5 or lower from all four measured sites differed significantly between the four versions (absolute difference 7.9 to 10.4%, P<0.00001). Small changes in the reference data used in T-score calculations had large effects on patient categorization and the calculated prevalence of osteoporosis. The impact of changes in reference data need to be carefully evaluated by users and manufacturers before widespread clinical dissemination.

Construction and validation of a population-based bone densitometry database.

Utilization of dual-energy X-ray absorptiometry (DXA) for the initial diagnostic assessment of osteoporosis and in monitoring treatment has risen dramatically in recent years. Population-based studies of the impact of DXA and osteoporosis remain challenging because of incomplete and fragmented test data that exist in most regions. Our aim was to create and assess completeness of a database of all clinical DXA services and test results for the province of Manitoba, Canada and to present descriptive data resulting from testing. A regionally based bone density program for the province of Manitoba, Canada was established in 1997. Subsequent DXA services were prospectively captured in a program database. This database was retrospectively populated with earlier DXA results dating back to 1990 (the year that the first DXA scanner was installed) by integrating multiple data sources. A random chart audit was performed to assess completeness and accuracy of this dataset. For comparison, testing rates determined from the DXA database were compared with physician administrative claims data. There was a high level of completeness of this database (>99%) and accurate personal identifier information sufficient for linkage with other health care administrative data (>99%). This contrasted with physician billing data that were found to be markedly incomplete. Descriptive data provide a profile of individuals receiving DXA and their test results. In conclusion, the Manitoba bone density database has great potential as a resource for clinical and health policy research because it is population based with a high level of completeness and accuracy.