[Changes in the prevalence of statin use in Germany - findings from national health interview and examination surveys 1997-1999 and 2008-2011].

BACKGROUND

Evidence-based guideline recommendations on lipid lowering drug treatment, in particular statin treatment, play an essential role in the management of dyslipidemias and in the prevention of cardiovascular disease events. In Germany, statutory health insurance data provide information on time trends in the prescription of lipid lowering drugs. However, population-based data regarding changes in user prevalence according to socio-demographic and health-related characteristics are lacking. Based on data from national health interview and examination surveys for adults in Germany 1997-1999 (GNHIES98) and 2008-2010 (DEGS1), the present analysis aims to close this information gap with a particular focus on the use of statins.

METHODS

The study population consisted of 7,099 participants (GNHIES98) and 7,091 participants (DEGS1) aged 18 to 79 years at the time of the respective surveys. Primary data on medication use within 7 days prior to the survey were collected using standardized medication interviews and brown-bag drug review. Unique product identifiers on original drug containers were scanned and coded according to the latest version of the Anatomical Therapeutic Chemical (ATC) classification system. Medical history was obtained in computer-assisted personal interviews. A history of stroke or coronary heart disease (CHD) was assessed among persons aged 40 to 79 years only, and previous stroke or CHD were defined as cardiovascular disease. Obesity was defined as a body mass index (BMI) of ≥ 30kg/m) based on calculation from standardized measures of body weight and height. Information on socio-demographic variables and type of health insurance was collected using standardized self-administered questionnaires. In cross-sectional descriptive analyses we calculated the prevalence of statin use (ATC codes: C10AA, C10BA, C10BX) by survey as well as the changes between surveys stratified according to relevant preexisting diseases and other co-variables. The association between survey period and statin use was analyzed in multivariable binary logistic regression models among persons aged 40 to 79 years. All results were weighted and standardized for the population of 2010.

RESULTS

Between the two survey periods 1997-1999 and 2008-2011, the prevalence of statin use increased from 3.2 % to 8.8 %. The increase was most pronounced for the age group 65 to 79 years (7.2 % vs. 26.9 %) and among persons with relevant preexisting conditions, such as CHD (19.1 % vs. 54.9 %), stroke (17.1 % vs. 50.1 %), diabetes mellitus (10.5 % vs. 33.2 %), and dyslipidemia (12.6 % vs. 27.8 %). Among persons aged 40 to 79 years, the prevalence of statin use significantly increased between the two surveys, independent of co-variables (Odds Ratio: 3.70; 95 % confidence interval [CI]: 2.92 to 4.70). This applied to persons with cardiovascular disease (5.17; 3.50 to 7.64) and without cardiovascular disease (2.76; 2.07 to 3.67).

CONCLUSION

The increase in the prevalence of statin use in Germany between the two national health surveys (1997-1999 and 2008-2011) reflects the implementation of current guideline recommendations without evidence for inequalities according to gender, education, type of health insurance or region of residence. These population-based data add to information on statin prescription obtained from statutory health insurance data. Limitations of survey-based information derive from potential misclassification and selection bias as well as large time gaps between the survey periods. Further studies are needed to examine why the observed prevalence of statin use among persons with cardiovascular morbidity lags behind current guideline recommendations for secondary cardiovascular prevention.