Predicting short-term blood pressure trajectories using lifestyle and behavioural factors: a prospective cohort study.

Background: Hypertension is a major contributor to cardiovascular morbidity and mortality. While lifestyle modification is central to prevention, evidence on short-term blood pressure (BP) dynamics in relation to behavioural factors remains limited. Objective: To evaluate the influence of diet, physical activity, and psychological stress on systolic blood pressure (SBP) trajectories and to develop a regression-based model for short-term BP prediction. Methods: In this 12-week prospective cohort study, 75 adults attending a preventive cardiology clinic were followed, with BP measured at baseline, 6 weeks, and 12 weeks using validated oscillometric methods. Lifestyle and behavioural factors were assessed using the Food Frequency Questionnaire (sodium intake and DASH adherence), IPAQ-SF (physical activity), and PSS-10 (stress). Linear mixed-effects regression identified predictors of SBP change, and Elastic Net regression predicted 12-week SBP. Results: Sixty-seven participants (mean age 44.6 ± 10.8 years; 52.2% male) completed follow-up. Mean SBP declined from 134.2 ± 12.6 to 131.4 ± 11.5 mmHg. Higher physical activity and DASH adherence were associated with SBP reduction, whereas higher sodium intake and stress predicted SBP elevation (all p < 0.05). The Elastic Net model demonstrated strong predictive performance (R 2 = 0.78; RMSE = 5.9 mmHg). Physical activity had a stronger effect in participants <45 years, and stress amplified sodium-related SBP increases. Conclusions: Short-term SBP trajectories are strongly influenced by modifiable behavioural factors. Predictive models based on lifestyle data may support early risk stratification and personalized hypertension prevention.