Comparison of high-frequency intensive balneotherapy with low-frequency balneotherapy combined with land-based exercise on postural control in symptomatic knee osteoarthritis: a randomized clinical trial.

Knee osteoarthritis (KOA) can generate postural control impairments which can increase fall risk. Land-based exercise (LBE) and balneotherapy are two modalities currently prescribed, but the impact of the latter on balance control has not been studied. This study aimed to compare two programs of balneotherapy with or without LBE to improve postural control, looking at frequency and duration of treatment. A total of 236 KOA patients (mean age = 64 years) were included in this prospective and randomized study: 122 patients went through 3 weeks of standardized continuous balneotherapy (high frequency/short duration) program (Gr1) and 114 went through 3 weeks of discontinuous (low frequency) balneotherapy program followed by 3 weeks of LBE (Gr2). The total number of treatment sessions was the same for both groups. Posturography was carried out before balneotherapy (W0) and at 3 (W3), 6 (W6), and 12 (W12) weeks after the beginning of treatment. Postural control increased in Gr1 from W0 to W3 and from W0 to W12 and in Gr2 from W0 to W6 and from W3 to W6. The improvement was greater in Gr1 from W0 to W3 and from W6 to W12 and in Gr2 from W3 to W6. High-frequency intensive balneotherapy improved posture control at 3 weeks, while low-frequency balneotherapy did not. This improvement persisted over a 12-week assessment period at the same level. LBE generated an improvement that did not persist over time. Sustained improvement of postural control requires high-frequency repetition of consecutive balneotherapy sessions.

Influence of meteorological elements on balance control and pain in patients with symptomatic knee osteoarthritis.

This study aimed to determine if pain and balance control are related to meteorological modifications in patients with knee osteoarthritis (OA). One hundred and thirteen patients with knee OA (mean age = 65 ± 9 years old, 78 women) participated in this study. Static posturography was performed, sway area covered and sway path traveled by the center of foot pressure being recorded under six standing postural conditions that combine three visual situations (eyes open, eyes closed, vision altered) with two platform situations (firm and foam supports). Knee pain score was assessed using a visual analog scale. Balance control and pain measurements recorded in the morning were correlated with the meteorological data. Morning and daily values for temperature, precipitation, sunshine, height of rain in 1 h, wind speed, humidity, and atmospheric pressure were obtained from the nearest data collecting weather station. The relationship between postural control, pain, and weather variations were assessed for each patient on a given day with multiple linear regressions. A decrease of postural stability was observed when atmospheric pressure and maximum humidity decreased in the morning (p < 0.05) and when atmospheric pressure decreased within a day (p < 0.05). Patient's knee pain was more enhanced when it is warmer in the morning (p < 0.05) and when it is wetter and warmer within a day (p < 0.05). The relationship between weather, pain, and postural control can help patients and health professionals to better manage daily activities.

Relation of arterial stiffness with postural control in older people.

PURPOSE: Arterial stiffness generates vascular alterations that may cause balance disorders and falls. This study aimed to investigate the possible link between arterial stiffness and postural control under different sensorial conditions in patients over 65 years. METHODS: Carotid-femoral pulse wave velocity (PWV) was measured in 47 participants aged over 65 years to evaluate their arterial stiffness (high PWV). Twenty-seven participants (mean age = 70.52 ± 4.02 years, 22 females) had a normal PWV (< 10 m s-1) and 20 participants (mean age = 75.93 ± 6.11 years; 15 females) had a high PWV (≥ 10 m s-1). Postural control was evaluated using a force platform in four postural conditions: eyes open (EO) 1, eyes closed (EC), eyes open with a dual task (DT) and eyes open again (EO2). Using sway path traveled and surface covered by the center of foot pressure, we calculate the length function of surface (LFS). This ratio provides information about the precision (surface) of postural control and the effort made (length) by the subjects. RESULTS: After an age-adjustment, LFS was lower in EO than in EC and DT in both groups (p ≤ 0.001). LFS was higher in participants with high PWV both in eyes open and eyes closed conditions (p < 0.05). LFS increased when PWV increased in EO (p < 0.01) and EC conditions (p < 0.001) but not when a dual task was performed. CONCLUSION: Difficulties in maintaining equilibrium under a dual-task condition are more pronounced in people with increased arterial stiffness. These data suggest that understanding of the influence of the arterial stiffness level on specific balance control parameters could contribute to propose better balance-oriented rehabilitation programs in older adults in an attempt to prevent fall.

Prevalence of hepatitis B and hepatitis C virus infections in France in 2004: social factors are important predictors after adjusting for known risk factors.

To monitor the prevalence of hepatitis B and hepatitis C a cross-sectional survey was conducted in 2004 among French metropolitan residents. A complex sampling design was used to enroll 14,416 adult participants aged 18-80 years. Data collected included demographic and social characteristics and risk factors. Sera were tested for anti-HCV, HCV-RNA, anti-HBc and HBsAg. Data were analyzed with SUDAAN software to provide weighted estimates for the French metropolitan resident population. The overall anti-HCV prevalence was 0.84% (95% CI: 0.65-1.10). Among anti-HCV positive individuals, 57.4% (95% CI: 43.2-70.5) knew their status. Factors associated independently with positive anti-HCV were drug use (intravenous and nasal), blood transfusion before 1992, a history of tattoos, low socioeconomic status, being born in a country where anti-HCV prevalence >2.5%, and age >29 years. The overall anti-HBc prevalence was 7.3% (95%: 6.5-8.2). Independent risk factors for anti-HBc were intravenous drug use, being a man who has sex with men, low socioeconomic status, a stay in a psychiatric facility or facility for the mentally disabled, <12 years of education, being born in a country where HBsAg prevalence >2%, age >29 and male sex. The HCV RNA and HBsAg prevalence were 0.53% (95% CI: 0.40-0.70) and 0.65% (95% CI: 0.45-0.93), respectively. Among HBsAg positive individuals, 44.8% (95% CI: 22.8-69.1) knew their status. Anti-HCV prevalence was close to the 1990s estimates whereas HBsAg prevalence estimate was greater than expected. Screening of hepatitis B and C should be strengthened and should account for social vulnerability.

Trends of the potentially inappropriate medication consumption over 10 years in older adults in the East of France.

PURPOSE: To describe the trends of potentially inappropriate medication (PIM) use in older adults from 1995 to 2004 in the East of France, by using the 1997 Beers criteria and its French update, and to assess risk factors for this PIM use. METHODS: We carried out a repeated cross-sectional study using data collected among people aged >/=65 years, examined in the Center for Preventive Medicine. Studied variables were socio-demographic, clinical data, medication consumption and the self-health status. Joinpoint regression analysis was used to estimate the temporal changes in PIM rate. RESULTS: 30 683 participants were included. 51.2% were women. The mean age was 70.1 +/- 4.3 years [65-99]. The annual overall rate of PIM use decreased significantly during the study period. These rates range from 14.9% in 1995 to 9.0% in 2004 according the Beers criteria (-3.4% per year) and from 33.5% in 1995 to 19.3% in 2004 according to the French update criteria (-3.6% per year). The annual rate of medication users increased during the same period (+0.75% per year). The risk of PIM consumption increased with age, number of drugs and frequency of the visits to the physician (OR = 1.26 [1.18-1.35]). This risk was also higher among women (OR = 1.29 [1.18-1.40]), elderly living alone (OR = 1.09 [1.02-1.17]) and with those with low education level (OR = 1.19 [1.02-1.38]). CONCLUSION: This study shows a decrease in PIM consumption. Despite an increase of drug use in the elderly, an improving of the quality of this consumption remains possible.

Clinical determinants of failure in balance tests in elderly subjects.

We assessed the role of clinical and biological parameters on performance in four balance tests in elderly subjects. An observational study was conducted in the Center for Preventive Medicine of Nancy (France) in 2368 community-living elderly subjects aged 60 and older. Body mass index (BMI), Mini-Mental State Examination (MMSE), clock test, "Health score" and use of psychotropic drugs (UPD) were assessed. Participants performed four balance tests: "one-leg-stand" (OLS), "timed-up-and-go" (TUG), "rise-from-the-floor" (RFF) and "sit-to-stand" (STS). The statistical analysis showed that women were almost twice as likely to fail balance tests as men. In both women and men, the following determinant factors of the performance in balance tests were found: for OLS: age, BMI and health score; for TUG: age, BMI, clock test and health score; for RFF: BMI and health score. In addition, in women other determinant factors were: MMSE for OLS, UPD for TUG, age and clock test for RFF. In men, the clock test and the UPD were also significant determinant factors for OLS. Similar results were found for STS. In conclusion, female sex, overweight, low cognitive status, low self-perception of health and UPD were associated with a higher risk of failure in balance tests.

[Alcohol, tobacco and colorectal adenomas and cancer. Case-control study in a population with positive fecal occult blood tests]. / Le tabac et l'alcool augmentent le risque d'adénomes et de cancers colorectaux. Etude comparant 3292 cas avec 5456 témoins dans une population à risque moyen ayant eu un test de dépistage de sang dans les selles positif.

OBJECTIVE: To analyze the associations between lifestyle factors and colorectal adenomas or cancers in a population 50-74 years old. METHOD: The study population underwent colonoscopy after positive fecal occult blood test in Health examination centers of the French general health insurance. The two sets of cases (n= 674 cancers, n=2618 adenomas) were compared with controls (n=5456). Associations between risk of colorectal disease and health data (mainly tobacco and alcohol consumption, physical activity, obesity, and laboratory test results) were analyzed with logistic regression models to estimate odds ratios. RESULTS: The probability of colorectal cancer or adenoma was statistically associated with age (60 years or older in men and women). A significant relation between these diseases was observed with smoking (in both smokers and ex-smokers) and with alcohol consumption, with odds ratios above 1.30. The other risk factors studied were not significantly associated with these colorectal diseases. CONCLUSION: This result provides still more evidence of the need for actions against these risk behaviors.

Comparison of an Innovative Rehabilitation, Combining Reduced Conventional Rehabilitation with Balneotherapy, and a Conventional Rehabilitation after Anterior Cruciate Ligament Reconstruction in Athletes.

BACKGROUND: Instability of the knee, related to anterior cruciate ligament injury, is treated by surgical reconstruction. During recovery, a loss of proprioceptive input can have a significant impact. Few studies have evaluated the benefits of rehabilitation of the knee in aquatic environment on functional outcomes. OBJECTIVE: This study aimed to compare an innovative rehabilitation protocol combining reduced conventional rehabilitation with aquatic rehabilitation, with a conventional rehabilitation, according to the National French Health Authority, in terms of kinetics, development of proprioceptive skills, and functional improvement of the knee. METHODS: 67 patients, who were amateur or professional athletes, were randomized into two groups: 35 patients followed the conventional rehabilitation protocol (Gr1) and 32 patients followed the innovative rehabilitation protocol (Gr2). Patients were evaluated before surgery, and at 2 weeks, 1, 2, and 6 months after surgery using posturography, and evaluation of muscular strength, walking performance and proprioception. This study is multicenter, prospective, randomized, and controlled with a group of patients following conventional rehabilitation (level of evidence I). RESULTS: For the same quality of postural control, Gr2 relied more on somesthesia than Gr1 at 6 months. The affected side had an impact on postural control and in particular on the preoperative lateralization, at 2 weeks and at 1 month. Lateralization depended on the affected knee, with less important lateralization in Gr2 preoperatively and at 1 month. The quadriceps muscular strength was higher in Gr2 than in Gr1 at 2 and 6 months and muscle strength of the external hamstring was greater in Gr2 than in Gr1 at 6 months. The isokinetic test showed a greater quadriceps muscular strength in Gr2. Gr2 showed a greater walking distance than Gr1 at one month. Gr2 showed an improvement in the proprioceptive capacities of the operated limb in flexion for the first 2 months. CONCLUSION: The effectiveness of the innovative rehabilitation program permits faster recovery, allowing for an earlier return to social, sporting, and professional activities. Faster retrieval of knee function following aquatic rehabilitation would prevent both short-term risk of lesions of the contralateral limb due to overcompensation and long-term risk of surgery due to osteoarthritis. REGISTRATION OF CLINICAL TRIALS: NCT02225613.

Colorectal cancer screening in Health Examination Centers.

OBJECTIVES: The aim of this study was to describe the results of colorectal cancer screening performed in the Health Examination Centers of the French general health insurance system. METHODS: The population consisted of 1,262,833 subjects (52.6% men) aged 50 to 74 years old who attended periodic health consultations from 1998 to 2003 in 89 Health Examination Centers in France. Subjects with increased risk for colorectal cancer and subjects with a positive fecal occult blood test (Hemoccult II') were invited to undergo colonoscopy. Subsequent follow-up and diagnostic data were collected. RESULTS: Prior screening practices for colorectal cancer (recent colonoscopy or fecal occult blood test, local screening campaign) were noted in 18% of the subjects attending Health Examination Center consultations. High risk for colorectal cancer (familial or personal factor) without ongoing surveillance or prior screening was observed in 3% of the study population. A fecal occult blood test was proposed to 79% of the population and of them, 89% effectively performed the test: 3.2% of tests were positive. A follow-up protocol was initiated for 63,357 subjects. A colonic exploration was performed in 69% of high-risk subjects and enabled detection of cancer in 85 and adenomas in 1683. A colonic exploration was performed in 88% of subjects with a positive fecal occult blood test and enabled detection of 674 cancers (positive predictive value of fecal occult blood test (PPV)=4.7%) including 174 Dukes A, and 2618 adenomas (PPV=18%) including 776 adenomas measuring more than 10 mm (PPV=5.4%). CONCLUSION: This study confirms the importance of implementing organized screening practices within Health Examination Centers before undertaking a generalized screen campaign targeting the entire French population.

Genetic and environmental contributions to serum retinol and alpha-tocopherol concentrations: the Stanislas Family Study.

BACKGROUND: Although numerous environmental factors are documented to influence serum retinol and alpha-tocopherol concentrations, little is known about the genetic versus the environmental contributions to variations in these traits. OBJECTIVE: The aim of this study was to estimate additive genetic heritability and household effects for serum retinol and alpha-tocopherol concentrations in a variance component analysis. DESIGN: In a sample of 387 French families, information on serum retinol and alpha-tocopherol concentrations, usual dietary intake, lifestyle, and serum lipid profiles and related polymorphisms (apolipoprotein E, apolipoprotein C-III, apolipoprotein B, cholesteryl ester transfer protein, and lipoprotein lipase) was obtained. RESULTS: For serum retinol--after adjustment for sex, age, body mass index, alcohol consumption, oral contraceptive use, and serum albumin, triacylglycerol, and apolipoprotein A-I concentrations--additive genetic effects and shared common environment contributed 30.5% and 14.2% of the total variance, respectively. For serum alpha-tocopherol, approximately 22.1% of the total variance was due to the additive effects of genes and 18.7% to those of household environment, after adjustment for the covariates sex, age, vitamin E intake, oral contraceptive use, and cholesterol, triacylglycerol, and apolipoprotein A-I concentrations. For both vitamins, the influence of measured polymorphisms was not significant. Moreover, heritability and household effect estimates were not significantly different between the 4 classes of relatives and did not vary significantly when families shared more meals at home. CONCLUSIONS: The results show that serum retinol and alpha-tocopherol concentrations are under genetic control in healthy families.

Moderate wine drinkers have lower hypertension-related mortality: a prospective cohort study in French men.

BACKGROUND: For a given blood pressure, the risk of death from coronary artery disease is much higher in northern Europe and the United States than in Mediterranean countries. OBJECTIVE: In this prospective cohort study, we tested the hypothesis that regular wine drinking reduces the hypertension-related risk of death. DESIGN: We used data from 36 583 healthy middle-aged men who had normal results on an electrocardiogram and were not taking drugs for cardiovascular disease risk factors. The subjects underwent a comprehensive health appraisal at the Center for Preventive Medicine between 1 January 1978 and 31 December 1985. Mortality from all causes and from specific causes during a 13-21-y follow-up was recorded. RESULTS: In a Cox model adjusted for 6 confounding variables, moderate wine drinkers (those who consumed <60 g alcohol/d and no beer) with systolic blood pressure (SBP) of 158, 139, or 116 mm Hg had significantly lower risks of death from all causes by 23%, 27%, and 37%, respectively, than did abstainers. Even for the highest quartile of blood pressure, moderate wine drinkers were protected from all-cause mortality. No significant reduction in all-cause mortality in relation to SBP was observed in other drinkers (those who consumed > or =60 g alcohol/d or who consumed beer and wine). CONCLUSION: A moderate intake of wine is associated with a lower risk of mortality from all causes in persons with hypertension.

Reliability of the Wisconsin Sleep Questionnaire: a French contribution to international validation.

We evaluated the reliability of a French version of the Wisconsin Sleep Questionnaire designed to investigate snoring, obstructive apnoeas, and sleeping problems. The assessment of reliability included the study of internal consistency and the 3 months repeatability of the questionnaire. The questionnaire was first completed at a Center of Preventive Medicine by a random sample of 122 subjects from the community. Three months later the same form was mailed and 82 questionnaires were returned (67.2%). No significant differences existed between responders and nonresponders for anthropometric data or life habits. The internal consistency in each domain was good or satisfactory (Cronbach's alpha=0.67 to 0.81). The concordance between the answers at a 3-month interval was excellent for questions on ever snoring, frequency of snoring, gasping/choking during sleep, and breathing stops during sleep (Cohen kappa>0.60). The questions on snoring loudness, a history of sleep apnoea, and excessive daytime sleepiness were fairly reproducible (kappa 0.28 to 0.60). We found no difference in reproducibility by gender or age. In conclusion, this reliability assessment in a sample of middle-aged subjects from the community in northeastern France showed satisfactory internal consistency and 3-months reproducibility of the main questions of a French translation of the Wisconsin Sleep Questionnaire.

Who are the "occasional" snorers?

STUDY OBJECTIVES: To assess the prevalence of occasional snoring in a group of middle-aged men, and to compare anthropometric variables and prevalence of sleep-related symptoms of subjects who occasionally snore with those of other snoring categories. DESIGN: A field survey of a sample of middle-aged men in France. PARTICIPANTS: Male employees of a local university and subjects from the community attending a preventive medicine center. Participation rate was 93.5%. MEASUREMENTS: Anthropometric variables were recorded in 499 subjects aged 23 to 66 years (mean, 44.3 years). The subjects completed a standard sleep questionnaire and were classified according to the snoring frequency as never, rarely, sometimes, occasional, several nights per week, and every night. The subjects who snore occasionally represented 8.6% of the total. RESULTS: The anthropometric data of subjects who snore occasionally were similar to those of subjects who habitually snore. When compared with subjects who do not snore, older age and a larger neck girth were significant. Subjects who snore occasionally were also significantly more often subjects who snore loudly, and tended more frequently to have breathing stops during sleep. CONCLUSIONS: Our epidemiologic study shows that approximately 9% of a sample of middle-aged men snore occasionally. Subjects who snore occasionally have anthropometric characteristics close to those of subjects who snore habitually. The prevalence of the main sleep-related symptoms is between that of subjects who do not snore and of subjects who snore habitually. In an epidemiologic setting, inclusion of subjects who snore occasionally as subjects who do not snore or subjects who snore habitually will lead to bias. The present results suggest they should be identified and considered as a separate category.

Lifestyle patterns concerning sports and physical activity, and perceptions of health.

OBJECTIVES: To explore the perceptions of health and physical activity, and the associations between these two areas from a theoretical lifestyle perspective. METHODS: Data was collected by means of a self-administered questionnaire, among 3019 adults attending centres for preventive medicine in France. Correspondence analysis examined the significance of the relationships between perceptions of health and perceptions of sports and physical activity. RESULTS: Four principal types of subjects emerged from the factor analyses expressing four different lifestyle patterns. "Non physically active lifestyle: a feeling of not being healthy", "Physically active lifestyle, pleasure/leisure-oriented", "Necessarily physically active lifestyle, regardless of health", "Physically active lifestyle aimed at stress relief". CONCLUSIONS: The sociological approach helps tackle sports and physical activity as behaviour patterns but also and especially as a health orientation connected with the socio-economical climate. This approach also gives sports practice back its meaningful cultural dimension.

The epidemiology of vertigo, dizziness, and unsteadiness and its links to co-morbidities.

Vertigo, dizziness, and unsteadiness (VDU) are common symptoms traditionally considered to result from different kinds of vestibular and non-vestibular dysfunctions. The epidemiology of each symptom and how they relate to each other and to migraine, agoraphobia, motion sickness susceptibility (MSS), vaso-vagal episodes (VVE), and anxiety-depression was the object of this population-based study in north-eastern France. A self-administered questionnaire was returned by 2987 adults (age span 18-86 years, 1471 women). The 1-year prevalence for vertigo was 48.3%, for unsteadiness 39.1%, and for dizziness 35.6%. The three symptoms were correlated with each other, occurred mostly (69.4%) in various combinations rather than in isolation, less than once per month, and 90% of episodes lasted ≤2 min. The three symptoms were similar in terms of female predominance, temporary profile of the episodes, and their link to falls and nausea. Symptom episodes of >1 h increase the risk of falls. VDU are much more common than the known prevalence of vestibular disorders. The number of drugs taken increase VDU even when controlling for age. Each VDU symptom was correlated with each co-morbidity in Chi-squared tests. The data suggest that the three symptoms are more likely to represent a spectrum resulting from a range of similar - rather than from different, unrelated - mechanisms or disorders. Logistic regressions controlling for each vestibular symptom showed that vertigo correlated with each co-morbidity but dizziness and unsteadiness did not, suggesting that vertigo is certainly not a more specific symptom than the other two. A logistic regression using a composite score of VDU, controlling for each co-morbidity showed a correlation of VDU to migraine and VVE but not to MSS and not to agoraphobia in men, only in women.

Relationship between the achievement of successive periodic health examinations and the risk of dying. Appraisal of a prevention scheme.

BACKGROUND: In the field of Periodic Health Examination (PHE), few studies brought information on their efficiency, both on morbidity and mortality. OBJECTIVE: The association between the reduction of mortality and a regular participation in PHE has been estimated. METHODS: This study concerned 50,116 persons 40-59 years old, of European origin, examined at the Centre of Preventive Medicine, Nancy, France, between 1 January 1980 and 31 December 1985 with a maximum duration of follow-up reaching 25 years. The risk of dying according to the number of examination was compared (Cox regression Model). The reduction in mortality (all causes as well as cancer and cardiovascular diseases) was significant for persons whose practice of the PHE continued for at least 10 years or more. The second approach used a propensity score. After stratification on the propensity score, the relative mortality risk of those who returned at least once (compared with never) for a new check-up was 0.75 (95% CI 0.69 to 0.82) in men and 0.89 (95% CI 0.78 to 1.02) in women. CONCLUSION: The survival analysis evidenced a significant reduction of all-cause mortality, as well as of cancer and cardiovascular-related mortality, in men and women having benefited from several PHEs. On the other hand, the Cox model by class of propensity score allowed to show a reduction in mortality only in men who returned at least once, in particular that of a higher health interest among the regular beneficiaries of PHE.

A simple clinical scale to stratify risk of recurrent falls in community-dwelling adults aged 65 years and older.

BACKGROUND: Correct identification of people at risk for recurrent falls facilitates the establishment of preventive and rehabilitative strategies in older adults. OBJECTIVE: The purposes of this study were: (1) to develop and validate a simple clinical scale to stratify risk for recurrent falls in community-dwelling elderly people based on easily obtained social and clinical items and (2) to evaluate the added value of 3 clinical balance tests in predicting this risk. DESIGN: This was a prospective measurement study. METHODS: A population of 1,618 community-dwelling people over 65 years of age underwent a health checkup, including performance of 3 clinical balance tests: the One-Leg-Balance Test, the Timed "Up & Go" Test, and the Five-Times-Sit-to-Stand Test. Falls were recorded using a self-administered questionnaire that was completed a mean (SD) of 25+/-5 months after the visit. Participants were randomly divided into either group A (n=999), which was used to develop the scale, or group B (n=619), which was used to prospectively validate the scale. RESULTS: Logistic regression analysis identified 4 variables that independently predicted recurrent falls in group A: history of falls, living alone, taking >or=4 medications per day, and female sex. Thereafter, 3 risk categories of recurrent falls (low, moderate, and high) were determined. Predicted probability of recurrent falls increased from 4.1% to 30.1% between the first and third categories. This scale subsequently was validated with great accuracy in group B. Only the Five-Times-Sit-to-Stand Test provided added value in the estimation of risk for recurrent falls, especially for the participants who were at moderate risk, in whom failure on the test (duration of >15 seconds) doubled the risk. LIMITATIONS: Falls were assessed only once, and length of follow-up was heterogeneous (18-36 months). CONCLUSIONS: Clinicians could easily classify older patients in low-, moderate-, or high-risk groups of recurrent falls by using 4 easy-to-obtain items. The Five-Times-Sit-to-Stand Test provides added value to stratify risk for falls in people at moderate risk.

Prevalence of factor V Leiden and prothrombin G20210A mutation in a large French population selected for nonthrombotic history: geographical and age distribution.

Among inherited risk factors for venous thrombosis, the most common are the FV-G1691A and FII-G20210A polymorphisms. The FV-G1691A polymorphism is preferentially observed in Europe, with differences between European countries. The FII-G20210A polymorphism is observed all over the world. The study was designed to compare the prevalence of the FV-G1691A and FII-G20210A polymorphisms in a large French population of unrelated individuals with no thrombotic disease history and to determine the age and geographical distributions. Over a period of 18 months, 6154 individuals were included throughout France and FV-G1691A and FII-G20210A polymorphisms were determined. The FV-G1691A prevalence was 3.84% (95% confidence interval 3.35-4.33) and the FII-G20210A prevalence was 3.07% (95% CI 2.63-3.51). A north-east/south-west gradient was observed in the FV-G1691A geographical distribution. No difference was observed in the geographical distribution of FII-G20210A polymorphism nor in the age distribution of the two polymorphisms. The prevalence of the two polymorphisms was similar whatever the blood group (O or non-O). Plasma D-dimers were significantly higher in healthy individuals with FV-G1691A but not in individuals with FII-G20210A. Thirty percent of variation in plasma prothrombin level was explained by environmental factors (serum cholesterol, age, oral contraception, hormonal replacement therapy, body mass index, sex) and genetic factors (FII-G20210A). As expected, individuals with FII-G20210A displayed higher plasma prothrombin level compared with individuals with wild type. However, this was not associated with a modification of the fibrin clot elastic modulus. This study shows a differential distribution of the two polymorphisms among the French territory. These polymorphisms confer a very mild hypercoagulable state as shown by the limited increased in basal D-dimers in mutated FV-G1691A populations and only a trend that does not reach statistical significance for FII-G20210A population.

Standardization of gamma-glutamyltransferase assays by intermethod calibration. Effect on determining common reference limits.

BACKGROUND: The improvement of the consistency of gamma-glutamyltransferase (GGT) activity results among different assays after calibration with a common material was estimated. We evaluated if this harmonization could lead to reference limits common to different routine methods. METHODS: Seven laboratories measured GGT activity using their own routine analytical system both according to the manufacturer's recommendation and after calibration with a multi-enzyme calibrator [value assigned by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference procedure]. All samples were re-measured using the IFCC reference procedure. Two groups of subjects were selected in each laboratory: a group of healthy men aged 18-25 years without long-term medication and with alcohol consumption less than 44 g/day and a group of subjects with elevated GGT activity. RESULTS: The day-to-day coefficients of variation were less than 2.9% in each laboratory. The means obtained in the group of healthy subjects without common calibration (range of the means 16-23 U/L) were significantly different from those obtained by the IFCC procedure in five laboratories. After calibration, the means remained significantly different from the IFCC procedure results in only one laboratory. For three calibrated methods, the slope values of linear regression vs. the IFCC procedure were not different from the value 1. The results obtained with these three methods for healthy subjects (n=117) were gathered and reference limits were calculated. These were 11-49 U/L (2.5th-97.5th percentiles). The calibration also improved the consistency of elevated results when compared to the IFCC procedure. CONCLUSIONS: The common calibration improved the level of consistency between different routine methods. It permitted to define common reference limits which are quite similar to those proposed by the IFCC. This approach should lead to a real benefit in terms of prevention, screening, diagnosis, therapeutic monitoring and for epidemiological studies.

Stepwise strategies in analysing haematuria and leukocyturia in screening.

The aim of the present work was to compare in a supposed healthy population of 680 subjects several algorithms for positive selection of urine samples requiring microscopic examination for erythrocytes and leukocytes after screening by automated test-strip measurement and particle counting on a Sysmex UF-50 flow cytometer. Four strategies have been formulated and the sensitivity, specificity, positive predictive value, negative predictive value, false positive rate, false negative rate, and microscopic review rate were measured. The strategy combining test strip analysis and automated counting on all samples, followed by microscopic examination of only discordant samples gave the best results. When the two methods of haematuria screening were in agreement (91% of samples), the false negative rate for microscopy was 1.1%, with a false positive rate of 0.8%, sensitivity of 66% and specificity of 99%, and the results are acceptable without any other examination. When the two methods of haematuria screening were discrepant, visual microscopic analysis was necessary to obtain definitive results. For leukocyturia screening, 80% of results were in agreement by test strip and automatic sediment urinalysis, with only ten results considered as false negatives (1.8%) and four as false positives (0.7%). Agreement was good and the other criteria were good (sensitivity 79%, specificity 99%). On conflicting samples, there was no agreement between methods and microscopic analysis was essential. The benefit of such an algorithm would be optimisation of the workflow without any loss of sensitivity and specificity at the expense of a two-fold increase in cost.