The two demographic factors most consistently linked to healthcare consumption are age and income level. These two variables shape how often people use health services, what types of care they seek, and how much they spend. While other demographic characteristics like gender, education, race, and geographic location also play a role, age and income stand out in health policy research as the primary drivers of utilization patterns.
Why Age Is the Strongest Predictor
Age influences healthcare consumption more than almost any other single variable. Adults 65 and older make up roughly 13.5% of the U.S. population but account for 45.2% of the top 10% of healthcare spenders. The gap in spending is dramatic: average total health spending for adults 65 and older reached $15,432 per person in 2023, compared to $4,144 for adults aged 19 to 34, according to KFF analysis of federal survey data.
This pattern holds across every type of service. In one study that grouped patients by utilization level, the highest-use group had a mean age of 67, averaged over 26 days of hospital stays per year, and filled nearly 49 prescriptions per person annually. The lowest-use group, with a mean age of 55, reported close to zero use of most healthcare services. The shift from low to high utilization tracks closely with the transition from middle age into the 65-and-older bracket, where chronic conditions accumulate and the body requires more frequent monitoring and treatment.
Age also determines the type of insurance coverage you carry, which in turn shapes how you access care. Among adults 18 to 29, about 15.4% are uninsured. That rate drops to 8.5% for those aged 45 to 64, and it falls even further after 65, when nearly everyone qualifies for Medicare. Insurance coverage directly affects whether people seek preventive care, manage chronic conditions, or delay treatment until problems become emergencies.
Gender introduces a notable wrinkle within age groups. Women in their 20s, 30s, and early 40s have higher health spending than men in the same age range, largely because of pregnancy and delivery-related care. After controlling for health status and other demographic variables, women still carry higher medical charges across primary care, specialty care, emergency treatment, and diagnostic services. The only category where spending evens out is hospitalizations.
How Income Shapes Access and Utilization
Income determines not just whether you can afford healthcare but what kind of healthcare you end up using. People living in the lowest-income neighborhoods visit doctors more frequently for conditions that could have been managed earlier or prevented entirely. A Canadian study found that residents of the poorest neighborhoods had ambulatory care visit rates two to three times higher than those in the wealthiest neighborhoods for conditions like asthma, congestive heart failure, and cellulitis. These are conditions where timely outpatient care can prevent complications, yet lower-income populations tend to present later and sicker.
Income also dictates how people interact with the healthcare system during disruptions. During the COVID-19 pandemic, higher-income patients shifted readily to telemedicine, while lower-income patients were more likely to continue using in-person outpatient visits. The median income of outpatient visitors dropped by $2,400 compared to pre-pandemic levels, suggesting that wealthier patients had more flexibility in how they received care. Whether lower-income patients chose in-person visits or simply lacked reliable internet access and devices for telehealth, the result was the same: income sorted people into different lanes of the healthcare system.
Employment status, which is tightly linked to income, plays a critical role through insurance. Among working-age adults, 76.8% of employed individuals have private insurance coverage, with 67% getting it through their employer. For unemployed adults, private coverage drops to 38.3%, and the uninsured rate jumps to 28%. People without insurance use fewer preventive services and are more likely to rely on emergency departments for conditions that a primary care visit could have addressed weeks earlier.
The Andersen Model Framework
Health researchers most commonly use the Andersen Behavioral Model to organize the factors that drive healthcare use. The model groups influences into three categories: predisposing factors (characteristics you already have before illness strikes), enabling factors (resources that make care possible), and need factors (actual health conditions). Age and gender fall squarely into the predisposing category, while income and insurance coverage are classified as enabling factors.
A systematic review of studies using this model found that age was examined in 11 out of 22 studies, making it the single most frequently studied predisposing factor. Gender appeared in 8 studies, as did education level. On the enabling side, income and insurance coverage appeared most often. In practice, predisposing and enabling factors interact constantly. A 70-year-old with Medicare and a pension uses healthcare very differently than a 70-year-old with no supplemental coverage and limited savings, even though they share the same age-related health risks.
Where Geography and Education Fit In
Two other demographic factors deserve mention because they amplify the effects of age and income. Geographic location, specifically whether you live in an urban or rural area, creates stark differences in healthcare access. Among elderly patients with ambulatory care expenses, rural residents averaged only 5.5 visits per year compared to 10.9 for metropolitan residents. Rural elderly also spent less than half as much on ambulatory care ($662 versus $1,432 to $1,687 in urban areas), not because they were healthier, but because providers and facilities were scarce.
Education level operates more indirectly. Higher education is associated with better health literacy, stronger problem-solving skills, and greater ability to navigate complex medical decisions. It also correlates with higher income and better employment, which feed back into insurance coverage and access. The National Academy of Medicine notes that education improves reading, math, and science literacy in ways that help people understand health priorities, follow treatment plans, and make informed choices about when and how to seek care. For non-native English speakers, education also helps overcome language barriers that can prevent people from understanding their health needs at all.
While all of these factors matter, age and income remain the two that health economists and policymakers return to most consistently. Age predicts what your body will need. Income predicts whether you can get it.