Abstract:
BACKGROUND : Blood pressure (BP) is known to increase
inevitably with age. Understanding the different ages at which
great gains could be achieved for intervention to prevent and
control BP would be of public health importance.
METHODS : Data collected between 2003 and 2014 from 1 969
women aged 22 to 89 years were used in this study. Growth
curve models were fitted to describe intra- and inter-individual
trajectories. For BP tracking, the intra-class correlation
coefficient (ICC) was used to measure dependency of observations
from the same individual.
RESULTS : Four patterns were identified: a slow decrease in
BP with age before 30 years; a period of gradual increase
in midlife up to 60 years; a flattening and slightly declining
trend; and another increase in BP in advanced age. These
phases persisted but at slightly lower levels after adjustment
for body mass index. Three groups of increasing trajectories
were identified. The respective number (%) in the low, medium
and highly elevated BP groups were 1 386 (70.4%), 482 (24.5%)
and 101 (5.1%) for systolic BP; and 1 167 (59.3%), 709 (36.0%)
and 93 (4.7%) for diastolic BP. The ICC was strong at 0.71 and
0.79 for systolic and diastolic BP, respectively.
CONCLUSION : These results show that BP preventative and
control measures early in life would be beneficial for control
later in life, and since increase in body mass index may worsen
hypertension, it should be prevented early and independently.
