Table 2.
Mean Values and Absolute Change in Clinical Measures and Health Outcomes with Medicaid Coverage.*
| Variable | Mean Value in Control Group | Change with Medicaid Coverage (95% CI)† | P Value |
|---|---|---|---|
| Blood pressure | |||
| Systolic (mm Hg) | 119.3±16.9 | −0.52 (−2.97 to 1.93) | 0.68 |
| Diastolic (mm Hg) | 76.0±12.1 | −0.81 (−2.65 to 1.04) | 0.39 |
| Elevated (%)‡ | 16.3 | −1.33 (−7.16 to 4.49) | 0.65 |
| Hypertension | |||
| Diagnosis after lottery (%)§¶ | 5.6 | 1.76 (−1.89 to 5.40) | 0.34 |
| Current use of medication for hypertension (%)§|| | 13.9 | 0.66 (−4.48 to 5.80) | 0.80 |
| Cholesterol** | |||
| Total level (mg/dl) | 204.1±34.0 | 2.20 (−3.44 to 7.84) | 0.45 |
| High total level (%) | 14.1 | −2.43 (−7.75 to 2.89) | 0.37 |
| HDL level (mg/dl) | 47.6±13.1 | 0.83 (−1.31 to 2.98) | 0.45 |
| Low HDL level (%) | 28.0 | −2.82 (−10.28 to 4.64) | 0.46 |
| Hypercholesterolemia | |||
| Diagnosis after lottery (%)§¶ | 6.1 | 2.39 (−1.52 to 6.29) | 0.23 |
| Current use of medication for high cholesterol level (%)§|| | 8.5 | 3.80 (−0.75 to 8.35) | 0.10 |
| Glycated hemoglobin | |||
| Level (%) | 5.3±0.6 | 0.01 (−0.09 to 0.11) | 0.82 |
| Level ≥6.5% (%)†† | 5.1 | −0.93 (−4.44 to 2.59) | 0.61 |
| Diabetes | |||
| Diagnosis after lottery (%)§¶ | 1.1 | 3.83 (1.93 to 5.73) | <0.001 |
| Current use of medication for diabetes (%)§|| | 6.4 | 5.43 (1.39 to 9.48) | 0.008 |
| Depression | |||
| Positive screening result (%)‡‡ | 30.0 | −9.15 (−16.70 to −1.60) | 0.02 |
| Diagnosis after lottery (%)§¶ | 4.8 | 3.81 (0.15 to 7.46) | 0.04 |
| Current use of medication for depression (%)§|| | 16.8 | 5.49 (−0.46 to 11.45) | 0.07 |
| Framingham risk score (%)§§ | |||
| Overall | 8.2±7.5 | −0.21 (−1.56 to 1.15) | 0.76 |
| High-risk diagnosis | 11.6±8.3 | 1.63 (−1.11 to 4.37) | 0.24 |
| Age of 50–64 yr | 13.9±8.2 | −0.37 (−2.64 to 1.90) | 0.75 |
Plus–minus values are weighted means ±SD. Where means are shown without standard deviations, they are weighted means. The effect of Medicaid coverage was estimated with the use of two-stage least-squares instrumental-variable regression. All regressions include indicators for the number of household members on the lottery list, and all standard errors were “clustered,” or adjusted to allow for arbitrary correction of error terms within households. For the blood-pressure measures, all regressions also included controls for age (with dummies for age decile) and sex. All analyses were weighted with the use of survey weights. The sample size was all 12,229 survey respondents for all measures except for the Framingham risk score. HDL denotes high-density lipoprotein.
For variables measured as percentages, the change is expressed as percentage points.
Elevated blood pressure was defined as a systolic pressure of 140 mm Hg or more and a diastolic pressure of 90 mm Hg or more.
This analysis was not prespecified.
A participant was considered to have received a diagnosis of a certain condition after the lottery if he or she reported a first diagnosis after March 2008 (the start of the lottery). A participant who received a diagnosis before March 2008 was not considered to have a diagnosis after the lottery.
A participant was considered to have received medication for the condition if one or more of the medications recorded during the interview was classified as relevant for that condition.
A high total cholesterol level was defined as 240 mg per deciliter (6.2 mmol per liter) or higher. A low HDL cholesterol level was defined as less than 40 mg per deciliter (1.03 mmol per liter). There was no separate measurement of low-density lipoprotein cholesterol.
A glycated hemoglobin level of 6.5% or higher is a diagnostic criterion for diabetes.
A positive result on screening for depression was defined as a score of 10 or higher on the Patient Health Questionnaire 8 (PHQ-8). Scores on the PHQ-8 range from 0 to 24, with higher scores indicating more symptoms of depression.
The Framingham risk score was used to predict the 10-year cardiovascular risk. Risk scores were calculated separately for men and women on the basis of the following variables: age, total cholesterol and HDL cholesterol levels, measured blood pressure and use or nonuse of medication for high blood pressure, current smoking status, and status with respect to a glycated hemoglobin level ≥6.5%. Framingham risk scores, which are calculated for persons 30 years of age or older, range from 0.99 to 30%. Samples sizes for risk scores were 9525 participants overall, 3099 participants with high-risk diagnoses, and 3372 participants with an age of 50 to 64 years. A high-risk diagnosis was defined as a diagnosis of diabetes, hypertension, hypercholesterolemia, myocardial infarction, or congestive heart failure before the lottery (i.e., before March 2008).