Objective: The blood pressure (BP) trend is shown to have seasonally fluctuated, and is affected by both personal physical and cognitive conditions. This study aimed to investigate the long-term benefits of a BP management programme with adjustment for year-round BP fluctuations among the elderly in Hong Kong. Design and method: Elderly participants with ages above 55 years were recruited from 76 elderly centres and were prospectively followed up between September 2016 and January 2020. Personal interviews were conducted to assess personal health conditions. Nursing calls and social worker engagement were offered for those with suboptimal BP readings. The inclusion criteria were the participants who reported more than 80% of weekly BP records in at least 2 years of follow-up. The seasonal BP fluctuations were adjusted by time series models and the overall BP treads were tested by the Mann-Kendall test. The logistic regression models were used to investigate both the physical and cognitive conditions for good BP management. Results: A total of 1,151 elderly participants with a mean age of 79 years were included in the study. Based on the trend testing by Mann-Kendall test, 553 (48%) participants were classified as improved BP trend, i.e. downward trends of BP records, and 598 (52%) were classified as having stable or deteriorated BP levels. The multivariate model showed that improved BP trends were associated with baseline systolic BP levels, (OR 1.03, 95% CI 1.02 - 1.04), cholesterol problems, and subjective memory complaints (OR 0.64, 95% CI 0.47 - 0.85) (Table 1). Compared with eating junk food every day, eating less than once a week were good for BP management. Conclusions: Seasonal blood pressure fluctuations always influence the performance of blood pressure management programmes. Time-series modelling is possible to figure out the real trend of personal blood pressure records after adjustment for seasonal effects. This study demonstrates that the long-term benefits of our blood pressure management programme were limited by the elderly with memory complaints. When we are offering blood pressure management programme, special arrangement is required for the participants with mild cognitive impairment or even dementia.