Global prevalence of nocturnal hypertension: systematic review and meta-analysis

BACKGROUND: Nighttime blood pressure (BP) is a stronger predictor of cardiovascular events than daytime BP. However, the global prevalence of nocturnal hypertension across different populations has not been previously described. This review estimates the global prevalence of nocturnal hypertension, offering insights to guide clinical practice, healthcare planning and future research. METHODS: For this systematic review and meta-analysis, we searched PubMed, EMBASE, CINAHL, and Scopus and included studies reporting the prevalence of nocturnal hypertension and non-dipping BP in adults, including studies published up to 12 December 2024. Study selection, data extraction, and risk of bias assessment were conducted independently by two reviewers, with discrepancies resolved by consensus. There were no language restrictions. Random-effects meta-analyses were used to estimate pooled prevalence across study populations. The review was pre-registered with PROSPERO (CRD42025625712). RESULTS: A total of 449 studies were included. The prevalence of nocturnal hypertension was 45% (95% confidence interval (CI): 39-51, I2=97.4%) in the general population and was higher among individuals with hypertension (57%, 95%CI: 54-60, I2=84.7%), and high-risk patients including diabetes mellitus (56%, 95%CI: 38-72, I2=97.1%), obstructive sleep apnoea (60%, 95%CI: 42-78, I2=93.0%), chronic kidney disease (64%, 95%CI: 53-73, I2=95.2%). The prevalence of isolated nocturnal hypertension in the general population was 23% (95%CI: 14-34; I2= 93.8%), while the prevalence of non-dipping was 39% (95%CI: 34-45, I2=95.4%) in the general population and was higher among individuals with hypertension (48%, 95%CI: 46-50, I2=90.5%) and in high-risk populations, including patients with diabetes mellitus (52%, 95%CI: 44-59, I2=89.9%), obstructive sleep apnoea (63%, 95%CI: 47-76, I2=89.8%), and chronic kidney disease (58%, 95%CI: 54-61, I2=90.3%). Substantial heterogeneity was observed across studies, and pooled prevalence estimates should be interpreted in the context of population and methodological differences. CONCLUSION: Nocturnal hypertension is common across populations and particularly prevalent among individuals with hypertension and high-risk conditions such as diabetes and chronic kidney disease. Despite available diagnostic tools and effective treatments to lower nighttime BP, it remains substantially underdiagnosed. Evidence demonstrating that targeted reduction of nocturnal BP improves long-term cardiovascular outcomes is still limited. Future work should focus on establishing the clinical effectiveness of screening, diagnosis, and treatment of nocturnal hypertension.