with significantly raised albuminuria. High dietary
sodium intake is hypothesized to cause arterial injury
without increasing blood pressure.16 Moreover, during
high sodium intake, renal blood flow decreases and
intra-glomerular pressure increases.16
Stress was the second predictor of albuminuria.
Hypotheses about the pathophysiology of albuminuria
suggest that increased levels of urinary albumin may
be related to inflammation, endothelial dysfunction or
abnormalities in the renin-angiotensin-aldosterone
system.5
These hypotheses may explain the impact of
stress on urinary albumin loss.
Blood pressure control and BMI were not
associated with albuminuria in this study. The possible
reason might be that the differences of the cut-off point
on blood pressure control and BMI for Asians, and the
average of blood pressure with previous studies.14, 17
Waist circumferences (WC) was not associated with
albuminuria. It might have been because a measurement
error of WC from the participants who tended to pull
in their abdomens.
The predictors of uncontrolled blood pressure:
The best predictors of uncontrolled blood pressure were
higher sodium intake, poor medication adherence, less
knowledge of hypertension, and stress—with 65.3%
overall predictive power (Table 4). According to the
Socio-Ecological Model, two predictors (knowledge
of hypertension and stress) were intrapersonal factors,
while sodium intake and medication adherence were
health behaviors. These predictors were at a microsystem
level that could affect blood pressure. Therefore, the
main influences on uncontrolled blood pressure were
the intrapersonal factors. This result can be explained from
a socio-ecological perspective—that health status is affected
by a variety of personal factors, including genetic heritage,
behavioral patterns, and psychological dispositions.12
Higher sodium intake was the strongest predictor
of uncontrolled blood pressure, even though some
data on sodium intake may be under-estimated by the
participants. This finding is consistent with previous
studies, where higher levels of sodium intake was
associated with uncontrolled blood pressure.18, 38 Most
participants in this study consumed more than the
recommended amount of sodium, with a mean intake
of 3324 + 1582 mg/d. Additionally, the data from
the 3-day food record showed that most participants
used seasonings and they preferred to buy food from
food shops rather than cooking at home. In the Thai
culture, food at food shops or food stalls is very salty,39
thus adding to the risk of participants that consumed
more than 2,400 mg/day.
Poor medication adherence was the second
predictor of uncontrolled blood pressure. This finding
was consistent with prior studies in which drug
compliance was associated with uncontrolled blood
pressure.9, 20 The goal of antihypertensive therapy is
achieve and maintain blood pressure control in order
to reduce the probability of future cardiovascular and
renal events. An approach to accomplishing these goals
is to increase adherence to treatment regimens among
the patients.40 Nevertheless, most of the participants
with low medical adherence revealed that “they were not
ill, and their blood pressure was normal level. Therefore,
they had no need to take medicine regularly.” Therefore,
the lack of symptoms of hypertension was found to
decrease adherence.
Lack of knowledge about hypertension was the
third predictor of uncontrolled blood pressure. This
finding was consistent with previous studies in which
knowledge of hypertension was associated with blood
pressure control.23,24 However, this was inconsistent
with another study11 that knowledge of hypertension
was not significantly related to blood pressure control,
even in rural contexts. It might be explained that most
respondents of those studies had good knowledge about
hypertension, or they had participated in some public
health education programs on hypertension prevention.
Stress was the fourth predictor of uncontrolled
blood pressure. This finding was homogenous with
previous studies that emphasized the idea that a stimulus
or circumstance causing such a condition or a daily life
event is associated with lack of blood pressure control.9
Predictors of Albuminuria and Uncontrolled Blood Pressure in People with Hypertension in The Community
146 Pacific Rim Int J Nurs Res • April - June 2015
Stress can cause high blood pressure which is explained
by its pathogenesis. Stress stimulates the over-activity
of the sympathetic nervous system and this brings about
an increase in arterial contractibility and leads to increased
vascular resistance. Moreover, stress can decrease the
filtration surface in the kidney resulting in sodium and fluid
volume thus increasing preload by raising cardiac output
and by disturbing the renin-angiotensin function.41
However, the rest of the personal factors (gender,
age, duration of hypertension, BMI, WC, attitude
toward hypertension, activities), health behaviors
(cigarette smoking, alcohol drinking, stress management,
and physical activity), family support and participation
in community were not significantly associated with
uncontrolled blood pressure. One possible reason might
be because of the community context, the way of life in
rural area in Thailand in which people engaged in such
physical activities in their daily life, and participated
in the community activities. Moreover, a culture of
the family in Thailand is expected a family member have
a good take care of their family members or parents.
Limitations
Limitations include the following: 1) the
charted blood pressure depended on the current blood
pressure measurement, and did not necessarily reflect
previous blood pressure levels found in the medical
records; 2) the determination of UACR was based on
a single urine specimen; 3) self-report of the 3-day food
record evaluating the sodium intake of people with
hypertension may have underestimated the ingredients
of the menu because Thai food and some households
in large families whose members eat together; and 4)
errors in measuring waist circumference from the
participants who trended to pull in their abdomens.
Conclusion and Recommendations
The prevalence rate of albuminuria among the
participants with known hypertension was 27.5% and
52.2% of participants with uncontrolled blood pressure.
The predictors of albuminuria were higher sodium
intake and stress. The predictors of uncontrolled blood
pressure were higher sodium intake, poor medication
adherence, low knowledge about hypertension, and
stress. Recommendations for nursing practice are as follows: the community health nurses should 1)
monitor persons with uncontrolled hypertension that
exhibit high sodium intake and implement interventions
in order to increase health awareness and promote low
sodium consumption; 2) coordinate with the physicians
in order to monitor albuminuria particularly regarding
those with high sodium intake and high stress; and 3)
collaborate with the community and local government
to initiate a campaign to raise community awareness.
In further studies, intervention programs to increase
the health awareness and promote low sodium consumption
should be implemented for people with hypertension
who have high sodium intake; and albuminuria should
be monitored regularly in people with uncontrolled
hypertension, high sodium consumption and high stress.
Acknowledgements: The authors would like to
express their gratitude to the Thailand Nursing and
Midwifery Council for the research scholarship. Sincere
appreciation is also given to all participants in this study.