Thiazide diuretics use & risk of falls & syncope among hypertensives: A retrospective cohort study

Background & Objectives Although thiazide diuretics are frequently used to treat hypertension, they may also raise the risk of syncope and falls. The purpose of this study was to look at the relationship between hypertension individuals' use of thiazide diuretics and falls or syncope. Methods This retrospective cohort study, conducted between March 2019 and March 2024, included 236 individuals with hypertension taking thiazides and 236 controls not taking thiazides. Data from electronic medical records were extracted, including demographic, clinical, laboratory, and outcome data. The main outcome was the occurrence of syncope episodes or falls. Logistic regression analyses examined associations between various factors and falls/syncope risk. Results The study included 236 study participants taking thiazides (118 men, 118 women) and 236 controls not taking thiazides (118 men, 118 women). Study participants taking thiazides had a higher prevalence of hyponatremia (57 study participants, 24.1% vs. 31 study participants, 13.1%), hypokalaemia (52 study participants, 22% vs. 32 study participants, 13.6%), hypercalcemia (37 study participants, 15.7% vs. 17 study participants, 7.2%), metabolic alkalosis (89 study participants, 37.7% vs. 52 study participants, 22%), acute kidney injury (59 study participants, 25% vs. 30 study participants, 12.7%), and chronic kidney disease (89 study participants, 37.7% vs. 59 study participants, 25%) compared to controls (all P<0.05). The prevalence of falls/syncope events was significantly higher in the thiazide group (76 study participants, 32.2%) compared to the non-thiazide group (46 study participants, 19.5%), with a P value of 0.002. Multivariate analysis showed increased falls/syncope risk with age [adjusted odds ratio (AOR)=1.38], congestive heart failure (AOR=2.12), longer thiazide duration (AOR=1.21), hyponatremia (AOR=1.68), hypokalaemia (AOR=1.72), metabolic alkalosis (AOR=1.68), acute kidney injury (AOR=1.85), and decreased eGFR (AOR=1.22 per 10 ml/min/1.73m2 decrease). Interpretation & Conclusion Thiazide diuretic use in hypertensive patients is related to syncope, potentially mediated by electrolyte disturbances and renal impairment. These results highlight the importance of careful monitoring and individualized treatment approaches when prescribing thiazide diuretics to hypertensive patients.