Table 2.
Effect of Dietary Sodium on Headache Status (Respondents Who Did Not Use Chronic Analgesics or Prescription Analgesics in Past Month, NHANES 1999–2004)
| Population distribution† | Crude (N = 8819) | Adjusted‡ (N = 8819) | ||||||
|---|---|---|---|---|---|---|---|---|
| Exposure category | % Headache YES | % Headache NO | Odds ratio | (95% CI) | P trend | Odds ratio | (95% CI) | P trend |
| Dietary sodium residuals | ||||||||
| 1st quartile | 23.6 | 21.4 | 1.00 | — | .0455 | 1.00 | — | .0503 |
| 2nd quartile | 22.1 | 21.1 | 0.95 | (0.78, 1.16) | 0.91 | (0.74, 1.10) | ||
| 3rd quartile | 24.8 | 24.4 | 0.92 | (0.74, 1.15) | 0.87 | (0.70, 1.08) | ||
| 4th quartile | 29.5 | 33.2 | 0.81 | (0.66, 0.99) | 0.81 | (0.66, 0.99) | ||
†Based on weighted frequencies.
‡Adjusted for age, sex, and BMI. Degree of correlation among independent variables was negligible.