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. 2019 Mar 4:11:217-228.
doi: 10.2147/CLEP.S186590. eCollection 2019.

Epidemiology of dementia: prevalence and incidence estimates using validated electronic health records from primary care

Anna Ponjoan  1   2   3 , Josep Garre-Olmo  2 , Jordi Blanch  1 , Ester Fages  1 , Lia Alves-Cabratosa  1 , Ruth Martí-Lluch  1   2   3 , Marc Comas-Cufí  1 , Dídac Parramon  1   4 , María Garcia-Gil  1 , Rafel Ramos  1   5
Affiliations

Epidemiology of dementia: prevalence and incidence estimates using validated electronic health records from primary care

Anna Ponjoan et al. Clin Epidemiol. .

Abstract

Purpose: Updated estimates of incidence and prevalence of dementia are crucial to ensure adequate public health policy. However, most of the epidemiological studies in the population in Spain were conducted before 2010. This study assessed the validity of dementia diagnoses recorded in electronic health records contained in a large primary-care database to determine if they could be used for research purposes. Then, to update the epidemiology of dementia in Catalonia (Spain), we estimated crude and standardized prevalence and incidence rates of dementia in Catalonia in 2016.

Methods: The System for the Development of Research in Primary Care (SIDIAP) database contains anonymized information for >80% of the Catalan population. Validity of dementia codes in SIDIAP was assessed in patients at least 40 years old by asking general practitioners for additional evidence to support the diagnosis. Crude and standardized incidence and prevalence (95% CI) in people aged ≥65 years were estimated assuming a Poisson distribution.

Results: The positive predictive value of dementia diagnoses recorded in SIDIAP was estimated as 91.0% (95% CI 87.5%-94.5%). Age-and sex-standardized incidence and prevalence of dementia were 8.6/1,000 person-years (95% CI 8.0-9.3) and 5.1% (95% CI 4.5%-5.7%), respectively.

Conclusion: SIDIAP contains valid dementia records. We observed incidence and prevalence estimations similar to recent face-to-face studies conducted in Spain and higher than studies using electronic health data from other European populations.

Keywords: accuracy; electronic medical record; family physician; positive predictive value; quality; real-world data.

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Conflict of interest statement

Disclosure The authors report no conflicts of interest in this work.

Figures

Figure 1
Figure 1
Definition of true and false cases of dementia. Abbreviations: DSM, Diagnostic and Statistical Manual of Mental Disorders; ICD10, International Classification of Diseases, Tenth revision.
Figure 2
Figure 2
Incidence rate (A) and prevalence (B) of dementia. Note: According to sex (green line, women; blue line, men; red line, overall population) by age-group in Catalan population aged at least 65 years.
See this image and copyright information in PMC

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