ABSTRACT
Background:
Masked hypertension is well known for its poor cardiovascular outcome. But clinical clues related to the masked hypertension and/or masked effect (ME) are rarely known. Physical activity and/or job stress are related to increased daytime blood pressure (BP). This study is to identify whether ME is caused by physical activity and/or job category.
Methods:
Physical activity using Actical and masked effect by clinic BP and ambulatory BP monitoring were applied to 167 person for this study.
Results:
Age of the subjects was 54.9±9.6 and 74 subjects were female (57.4%). Field worker was 81 (48.5%) and office worker was 86 (51.5%). Clinic BP was 125.8±14.3 mmHg/ 79.8 ±10.9 mmHg in male and 119.0±14.0 mmHg/ 74.2 ±8.9 mmHg in female (p =0.03). Daily energy expenditure representing physical activity was 1,831.1±420.4 kcal. ME for systolic BP was 11.0 ±11.1 mmHg and ME for diastolic BP was 3.9 ±8.0 mmHg. In multiple linear regression adjusted by smoking and antihypertensive medication showed that clinic systolic BP was the only significant factor related to the ME (β =-0.44755, p< 0.0001 in male, β =-0.396, p <0.0001 in female). Physical activity or job category was not related to ME.
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Table 1.
General characteristics of the study subjects in number
Table 2.
Physical activities according to the job status and gender
Overall (n=167) | Men(n=80) | Women(n=87) | p-value | |
---|---|---|---|---|
PA by questionnaire* (kcal/day) | 2076.1 ± 793.5 | 2251.2 ± 841.8 | 1911.3 ±710.1 | 0.030 |
Field worker | 2043.2 ± 794.4 | 2277.1 ± 876.8 | 1828.7 ±650.5 | 0.010 |
Officer | 2115.2 ± 795.4 | 2232.4 ± 819.4 | 1994.2 ±760.9 | 0.040 |
PA by Actical† (kcal/day) | 1831.1 ± 420.4 | 2004.2 ± 444.9 | 1666.9 ±319.4 | 0.001 |
Field worker | 1759.1 ± 455.8 | 1883.2 ± 498.4 | 1646.6 ±385.2 | 0.001 |
Officer | 1897.2 ± 375.8 | 2109.2 ± 366.3 | 1684.9 ±243.3 | 0.001 |
Table 3.
Distribution of clinic blood pressure, ambulatory blood pressure, and masked effect
Table 4.
Univariate regression between masked effects and the study parameters
Men(n=80) | Women(n=87) | |||
---|---|---|---|---|
ME in SBP(mm Hg) | ME in DBP(mm Hg) | ME in SBP(mm Hg) | ME in DBP(mm Hg) | |
B‡ | B‡ | B‡ | B‡ | |
Age | ||||
≥65 yr | 3.280 | -1.163 | -1.044 | -1.096 |
<65 yr | 0.652 | -7.168* | 1.157 | -3.041 |
Job | ||||
Field worker | -1.692 | -6.644* | -0.176 | 0.785 |
Office worker | 1.597 | 0.021 | -5.391 | -1.292 |
PA by questionnaire (kcal/day) | -0.788 | -0.888 | 1.132 | -2.085 |
PA by Actical§ (kcal/day) | -0.133 | 0.006 | -0.466 | 0.206 |
Clinic SBP (mm Hg) | 0.444† | 0.133 | 0.403† | 0.149* |
BMI (kg/m2) | 1.539 | 3.794 | 4.055 | 5.564† |
Table 5.
Multiple linear regression analysis on masked effect by the study parameters with adjustment of smoking status and anti-hypertension medication status
Men(n=80) | Women(n=87) | |||
---|---|---|---|---|
ME in SBP(mm Hg) | ME in DBP(mm Hg) | ME in SBP(mm Hg) | ME in DBP(mm Hg) | |
B§ | B§ | B§ | B§ | |
Age | ||||
≥65 yr | -0.671 | 0.755 | 4.198 | 4.321* |
<65 yr | -0.764 | 3.982 | 2.707 | 7.092† |
Job | ||||
Field worker | 2.482 | 3.455 | 2.046 | -1.316 |
Office worker | -0.614 | -2.321 | 5.987 | 0.674 |
PA by questionnaire (kcal/day) | 0.966 | 0.296 | -0.430 | 2.828 |
PA by Actical∥ (kcal/day) | 0.133 | 0.262 | -0.331 | 0.468 |
Clinic SBP (mm Hg) | -0.447‡ | -0.102 | -0.396‡ | -0.150† |
BMI (kg/m2) | -1.645 | -2.539 | -3.559 | -5.511‡ |