Orthostatic blood pressure drop and cardiovascular and psychotropic medication dosages in acutely ill geriatric inpatients.

Objectives: . To investigate the dose-response relationship between cardiovascular or psychotropic medication dosages and falling orthostatic blood pressure in geriatric inpatients.

Methods: . This cross-sectional study included 100 consecutive geriatric inpatients of a Belgian hospital. The end points were the maximum changes of systolic (sBP) and diastolic (dBP) blood pressure in a standing up position at one or three minutes. The dosages of six classes of vascular and five classes of psychotropic medications were expressed in terms of a proportion of defined daily doses (DDD). Bivariate and multivariate linear regression models were used.

Results: . The 100 geriatric patients (85 ± 5 years, 58 % women) received 7.7 ± 4 medications (mean DDD: vascular = 1.0, psychotropic = 0.74) on the day of an orthostatic test (lying sBP: 136 ± 21; dBP: 72 ± 14 mm Hg). In a standing position, sBP and dBP fell by 12 ± 17 and 11 ± 5 mmHg, respectively. At the individual level, BP change was not correlated with vascular DDD (sBP: p = 0.07, r² = 0.04; dBP: p = 0.59; r² = 0.004) nor with psychotropic DDD (sBP: p = 0.14, r² = 0.02; dBP: p = 0.82; r² = 0.0). In multivariate analysis, sBP drop was positively associated with age, diabetes, falls history, and number of medications, but not with the DDD of any of the medication classes, while dBP drop was positively associated with age, diabetes, stroke and anaemia, but again with the DDD of any of the medication classes.

Conclusion: . No correlation was found between vascular and psychotropic medication dosages and the orthostatic blood pressure drop expressed as a continuous variable.