Prevalence and incidence of young onset dementia and associations with comorbidities: A study of data from the French national health data system.

BACKGROUND: Dementia onset in those aged <65 years (young onset dementia, YOD) has dramatic individual and societal consequences. In the context of population aging, data on YOD are of major importance to anticipate needs for planning and allocation of health and social resources. Few studies have provided precise frequency estimates of YOD. The aim of this study is to provide YOD prevalence and incidence estimates in France and to study the contribution of comorbidities to YOD incidence. METHODS AND FINDINGS: Using data from the French national health data system (Système National des Données de Santé, SNDS) for 76% of the French population aged 40 to 64 years in 2016 (n = 16,665,795), we identified all persons with dementia based on at least 1 of 3 criteria: anti-Alzheimer drugs claims, hospitalization with the International Classification of Diseases-10th Revision (ICD-10) dementia codes (F00 to F03, G30, G31.0, G31.1, or F05.1), or registration for free healthcare for dementia. We estimated prevalence rate (PR) and incidence rate (IR) and estimated the association of comorbidities with incident YOD. Sex differences were investigated. We identified 18,466 (PRstandardized = 109.7/100,000) and 4,074 incident (IRstandardized = 24.4/100,000 person-years) persons with prevalent and incident YOD, respectively. PR and IR sharply increased with age. Age-adjusted PR and IR were 33% (95% confidence interval (CI) = 29 to 37) and 39% (95% CI = 31 to 48) higher in men than women (p < 0.001 both for PR and IR). Cardio- and cerebrovascular, neurological, psychiatric diseases, and traumatic brain injury prevalence were associated with incident YOD (age- and sex-adjusted p-values <0.001 for all comorbidities examined, except p = 0.109 for antihypertensive drug therapy). Adjustment for all comorbidities explained more than 55% of the sex difference in YOD incidence. The lack of information regarding dementia subtypes is the main limitation of this study. CONCLUSIONS: We estimated that there were approximately 24,000 and approximately 5,300 persons with prevalent and incident YOD, respectively, in France in 2016. The higher YOD frequency in men may be partly explained by higher prevalence of cardiovascular and neurovascular diseases, substance abuse disorders, and traumatic brain injury and warrants further investigation.

Rapid and large-scale implementation of HCV treatment advances in France, 2007-2015.

BACKGROUND: The last decade was marked by major advances in HCV treatment with the introduction of first wave protease inhibitors (1st-wave PIs, telaprevir or boceprevir) in 2011 and second direct-acting antivirals (2nd-wave DAAs) in 2014, that followed low effective pegylated interferon α / ribavirin bitherapy. We estimated the number of patients initiating HCV treatment in France between 2007 and 2015 according to the type of therapy, described their demographical characteristics, and estimated how many were cured with 2nd-wave DAAs in 2014-2015. METHODS: Individual data from the national health insurance information system were analysed. HCV treatment initiation was defined as a drug reimbursement in the absence of any reimbursement for the same drug in the previous six weeks. RESULTS: Between 2007 and 2015, 72,277 patients initiated at least one HCV treatment. The annual number of patients initiating treatment decreased from 2007 (~13,300) to 2010 (~10,000). It then increased with the introduction of 1st-wave PIs (~12,500 in 2012), before decreasing again in 2013 (~8400). A marked increase followed upon the approval of 2nd-wave DAAs in 2014 (~11,600). Approximately, 8700 and 14,700 patients initiated 2nd-wave DAAs in 2014 and 2015, respectively, corresponding to an estimated 20,300 cured patients in 2014-2015. Patients initiating HCV treatment were mostly male (~65% throughout the 9-year period). Women were older than men (mean age: 55.0 vs. 48.9). Increasing age was associated with more advanced treatment. Among patients initiating 2nd-wave DAAs, the proportions of those under 40 and over 79 years old increased between 2014 and 2015, whereas the proportion of those previously treated for HCV 2007 onwards declined. CONCLUSIONS: Successive advances in HCV treatment have been rapidly and widely implemented in France. With the announcement of universal access to DAAs in mid-2016 and price reductions, access to 2nd-wave DAAs is expected to expand even more.

Parkinson disease male-to-female ratios increase with age: French nationwide study and meta-analysis.

BACKGROUND: Parkinson's disease (PD) is 1.5 times more frequent in men than women. Whether age modifies this ratio is unclear. We examined whether male-to-female (M-F) ratios change with age through a French nationwide prevalence/incidence study (2010) and a meta-analysis of incidence studies. METHODS: We used French national drug claims databases to identify PD cases using a validated algorithm. We computed M-F prevalence/incidence ratios overall and by age using Poisson regression. Ratios were regressed on age to estimate their annual change. We identified all PD incidence studies with age/sex-specific data, and performed a meta-analysis of M-F ratios. RESULTS: On the basis of 149 672 prevalent (50% women) and 25 438 incident (49% women) cases, age-standardised rates were higher in men (prevalence=2.865/1000; incidence=0.490/1000 person-years) than women (prevalence=1.934/1000; incidence=0.328/1000 person-years). The overall M-F ratio was 1.48 for prevalence and 1.49 for incidence. Prevalence and incidence M-F ratios increased by 0.05 and 0.14, respectively, per 10 years of age. Incidence was similar in men and women under 50 years (M-F ratio <1.2, p>0.20), and over 1.6 (p<0.001) times higher in men than women above 80 years (p trend <0.001). A meta-analysis of 22 incidence studies (14 126 cases, 46% women) confirmed that M- F ratios increased with age (0.26 per 10 years, p trend=0.005). CONCLUSIONS: Age-increasing M-F ratios suggest that PD aetiology changes with age. Sex-related risk/protective factors may play a different role across the continuum of age at onset. This finding may inform aetiological PD research.

French colorectal cancer screening pilot programme: results of the first round.

OBJECTIVES: In France, a national pilot population-based screening programme on colorectal cancer was set up in 2002. In 2006, 23 French districts were included, targeting a population of more than five million people. This programme offers biennial screening using the fecal occult blood test (FOBT) to average risk subjects aged between 50 and 74 years. People receive a letter inviting them to consult their GPs, who in turn provide the FOBT. People with a positive test result are proposed a full colonoscopy. The results of the programme's first-round performance indicators are presented. METHODS: The monitoring centre collected data from GPs and gastroenterologists on follow-up and colonoscopy results for people who were screened positive. Data were transferred to the French Institute for Public Health Surveillance (InVS) for the analysis. RESULTS: The overall participation rate for the 19 districts having completed a first screening round reached 42%. The overall positive test rate was 2.7%. In the eight districts with comprehensive follow-up data for the first round, 86% of colonoscopies were completed after a positive test. A total of 1615 people were diagnosed with cancer, and 4612 people with adenoma. The cancer detection rate reached 2.3/1000 [corrected] it was higher in men than in women (3.4/1000 [corrected] versus 1.4/1000) [corrected] and increased with age. Forty-three percent of invasive detected cancers were stage I, 24% stage II, 23% had lymph node involvement and 10% presented with distant metastasis. CONCLUSION: These results suggest that indicators are consistent with international references. During 2007-2008, the programme coverage will be progressively extended, and all 99 French districts should be actively involved in its implementation.

Relevance of healthcare reimbursement data to monitor syphilis epidemic: an alternative surveillance through the national health insurance database in France, 2011-2013.

OBJECTIVE: In France, surveillance of early syphilis (primary, secondary and early latent) relies on the clinician-based ResIST sentinel network. Although ResIST enables the monitoring of trends, a complete picture of the syphilis epidemic is not possible. More specifically, cases reported by this network are mostly diagnosed in free sexually transmitted infection clinics and hospitals (75% and 24%, respectively). This study aims to estimate the number and rate of diagnoses made outside these health facilities by exploring health insurance data. METHODS: An algorithm combining healthcare reimbursements for specific diagnostic tests and recommended treatment was fitted to identify syphilis cases. Sensitivity analyses were used to validate the algorithm. Age-standardised and gender-standardised diagnosis rates were estimated using census data. RESULTS: Between 2011 and 2013, 12 644 (7.5 cases per 100 000 inhabitants) reimbursements were made for syphilis-related diagnoses. The annual number of cases increased by 22% from 2011 (n=3771, rate=6.7/100 000) to 2013 (n=4589, rate=8.2/100 000). The rate of syphilis diagnosis increased in men from 12.9/100 000 to 16.0/100 000, while it remained steady in women at approximately 1.8/100 000. The disease burden was greatest in French overseas territories (18.1/100 000) and in the Paris area (11.7 cases/100 000). CONCLUSION: Despite the lack of data on the number of confirmed diagnoses and information on sexual behaviour, these findings demonstrate the relevance of analysing insurance data to help monitor the syphilis epidemic in patients who visit general practitioners and non-hospital-based specialists. Thus, reimbursement database might be a relevant alternative source of continuous information on syphilis in countries with similar insurance-based healthcare systems.

Cancer incidence estimation at a district level without a national registry: a validation study for 24 cancer sites using French health insurance and registry data.

BACKGROUND: District-level cancer incidence estimation is an important issue in countries without a national cancer registry. This study aims to both evaluate the validity of district-level estimations in France for 24 cancer sites, using health insurance data (ALD demands--Affection de Longue Durée) and to provide estimations when considered valid. Incidence is estimated at a district-level by applying the ratio between the number of first ALD demands and incident cases (ALD/I ratio), observed in those districts with cancer registries, to the number of first ALD demands available in all districts. These district-level estimations are valid if the ratio does not vary greatly across the districts or if variations remain moderate compared with variations in incidence rates. METHODS: Validation was performed in the districts covered by cancer registries over the period 2000-2005. The district variability of the ALD/I ratio was studied, adjusted for age (mixed-effects Poisson model), and compared with the district variability in incidence rate. The epidemiological context is also considered in addition to statistical analyses. RESULTS: District-level estimation using the ALD/I ratio was considered valid for eight cancer sites out of the 24 studied (lip-oral cavity-pharynx, oesophagus, stomach, colon-rectum, lung, breast, ovary and testis) and incidence maps were provided for these cancer sites. CONCLUSION: Estimating cancer incidence at a sub-national level remains a difficult task without a national registry and there are few studies on this topic. Our validation approach may be applied in other countries, using health insurance or hospital discharge data as correlate of incidence.

Are breast cancer screening practices associated with sociodemographic status and healthcare access? Analysis of a French cross-sectional study.

The aim of this study was to analyse the role of women's sociodemographic and healthcare access characteristics according to breast cancer screening practices (organized, individual or no screening). A cross-sectional study was set up in seven French districts using a self-administered postal questionnaire. Randomization was stratified proportionally on age and urban/rural status in each district separately among attendees and nonattendees to the organized breast cancer screening programme (OS). A total of 5638 women aged 50-74 years returned their questionnaires: 1480 in the attendee OS group and 4158 in the nonattendee group. Among them, 3537 declared having undergone a recent mammography outside the organized programme (individual, IS group) and 621 declared never having undergone a mammography or having done so more than 2 years ago (NS group). Analyses showed a gradient between the three groups (IS, OS and NS, respectively) in their association with breast cancer screening practices considering three factors: an increasing gradient was observed for renunciation of basic healthcare for financial reasons, a decreasing gradient in the regular visit to a medical gynaecologist and having had a Pap smear in the last 3 years. Three other variables that showed a decreasing gradient are: living with a partner, current use of hormone replacement therapy and having had a check-up in the last 5 years. In conclusion, the main differences between breast cancer screening practices were largely associated with difficulties in healthcare access, considering regular gynaecological visits in particular.