Stress and blood pressure in Kuna Amerinds

Abstract

Is migration from isolated indigenous island communities to Panama City associated with an increase in stress? Individuals were randomly sampled from two Kuna communities: 325 individuals in Panama City and 133 on a Caribbean island. Stress was assessed through the Milcom questionnaire, which explores physical symptoms and symptoms relevant to mood and emotional state, and Cantril's ladder, which examines life satisfaction. Physical symptoms were more common in the urban community (p < 0.001), and complaints reflecting mood were also significantly higher on the mainland (p < 0.001); the two measures were highly correlated. While systolic and diastolic blood pressure was higher in the mainland community (p < 0.001), there was no relation between blood pressure level and any index of stress. Despite unambiguous evidence of an increase in stress in migrants to the city, there was no indication that the stress contributed to the rise in blood pressure level. Migration to an urban setting is associated with an increase in physical symptoms and symptoms reflecting depressed mood, suggesting increased stress level. Life satisfaction is less influenced, possibly providing a measure of the degree of stress.

Figure 1

Comparison of the number of positive (symptom present) responses to the 135 questions in the Milcom questionnaire, comparing responses in the suburban village (Abayala) and the indigenous, isolated location (Ailigandi). Differences between the two locations and the total number of positive responses (those reflecting physical symptoms and those involving mental state or mood) were all highly significant (p<0.001).

Figure 2

Relation between total number of positive responses to the 119 questions involving physical symptoms and the number of positive responses to the mental or mood questions in the same individual. Because 458 individuals were involved, average values by cohort by decade have been presented. The correlation is highly significant (r=0.97; p<0.001).

Figure 3

Frequency distribution of responses to the Cantril ladder query in the isolated indigenous village (Ailigandi) and the mainland suburban community (Abayala). Both distributions have the anticipated mode of 5 but are highly skewed, with very few responses below 5 (p<0.01). The two distributions are statistically different (χ²=13.3; p<0.01), with more of the Abayala participants at the mode level 5 and statistically fewer above that level (p<0.001).

Figure 4

Systolic blood pressure (SBP) distributions in Ailigandi and Abayala. Many more inhabitants of suburban, mainland Abayala bad an SBP >120 mm Hg (22.2%) than in isolated, indigenous Ailigandi (6.8%; p<0.001). All 16 participants with SBP >140 mm Hg (not shown) resided in Abayala.