The rising incidence of shingles with age
While anyone who has had chickenpox can get shingles, older adults face a substantially higher risk due to immunosenescence, the age-related decline of the immune system. A weakening immune system allows the dormant varicella-zoster virus (VZV) to reactivate and cause the painful shingles rash. This is why public health organizations, like the CDC, specifically target older age groups with vaccine recommendations.
Incidence rates for adults over 70
Data from various studies highlight the dramatic increase in shingles incidence with age. While population-wide figures offer a broad overview, a closer look at specific age bands reveals how risk accelerates for people over 70.
- 70–79 years: Research indicates a significant rise in incidence rates for individuals in this age group compared to younger cohorts. One study from 2015 showed that the rate was 8.35 per 1,000 person-years for those aged 70–79, compared to 6.52 per 1,000 for the 60–69 age group.
- Over 80 years: The trend continues for the very elderly, with a 2015 study citing an incidence rate of 10.70 per 1,000 person-years for patients 80 and older. Some health authorities estimate that about half of all people who live to age 85 will experience shingles during their lifetime.
Why risk increases with age
Several biological factors contribute to the higher likelihood of developing shingles as one gets older:
- Weakening immune system: As people age, the cellular immunity that keeps the VZV in check begins to wane. This reduced immune surveillance provides an opportunity for the dormant virus to reactivate and travel along nerve pathways to the skin, causing the characteristic rash.
- Underlying health conditions: Chronic illnesses such as diabetes, cancer, or HIV can further compromise the immune system, increasing the risk of shingles at any age, but particularly in older adults.
- Stress: High levels of physical and psychological stress can weaken the immune response, also making older adults more susceptible to the virus's reactivation.
Comparison of shingles risk factors
| Risk Factor | Risk Level for Young Adults (Under 50) | Risk Level for Adults Over 70 | Key Differences |
|---|---|---|---|
| Immune System | Generally robust, effectively suppresses the varicella-zoster virus (VZV). | Naturally weakened over time (immunosenescence), making viral reactivation more likely. | Age-related decline in immune function is the primary distinction, leading to higher rates in older adults. |
| Incidence | Rare, especially in healthy individuals. Reactivation is less common. | Significantly higher, with rates increasing with each decade. Approximately half of all cases occur after age 60. | The sheer frequency of outbreaks is much higher in the elderly due to weakened immunity. |
| Complications (e.g., PHN) | Risk is low; if it occurs, symptoms are typically less severe and shorter in duration. | Risk for long-term nerve pain (postherpetic neuralgia or PHN) is substantially higher and more severe. | The severity and duration of painful complications are significantly worse in the elderly due to nerve damage and slower recovery. |
| Medical Treatments | Often responds well to antiviral therapy initiated early. | Early antiviral treatment is crucial but may have a more limited effect on mitigating severe, long-term pain. | Older adults may require more aggressive pain management, and delayed treatment is more likely to result in complications. |
| Vaccination | Not routinely recommended for healthy individuals. | Highly recommended by public health authorities like the CDC to prevent or reduce the severity of shingles. | The vaccine is the most effective preventative measure available for older adults, who are most at risk. |
Prevention and management strategies for older adults
For older adults, preventing shingles is a key priority, especially given the increased risk of severe complications like postherpetic neuralgia (PHN), which causes chronic nerve pain.
- Vaccination: The most effective preventative measure is the recombinant zoster vaccine (RZV), known as Shingrix. The CDC recommends two doses for all healthy adults aged 50 and older. Vaccination is highly effective, providing strong protection against both shingles and PHN.
- Early diagnosis: If shingles symptoms appear, prompt medical attention is critical. Antiviral medications, such as acyclovir, famciclovir, or valacyclovir, can be prescribed and are most effective when started within 72 hours of the rash appearing.
- Pain management: Treatment for the acute pain and potential PHN may involve prescription pain relievers, numbing patches (lidocaine), or nerve blocks. Non-drug options like cool compresses and soothing baths can also provide relief.
- Support for the immune system: Maintaining a healthy lifestyle with a balanced diet, regular exercise, and effective stress management can support overall immune function.
Conclusion
In conclusion, the percentage of people over 70 who get shingles is difficult to pinpoint with a single number, but the risk and incidence rate increase significantly with age, with some studies showing rates over 8 per 1,000 person-years. This increased susceptibility is primarily due to the natural weakening of the immune system over time, making it easier for the dormant chickenpox virus to reactivate. For adults over 70, the risk is not just in developing shingles, but in experiencing more severe and prolonged symptoms and a higher rate of complications, particularly postherpetic neuralgia. Fortunately, highly effective vaccination options like Shingrix are available and strongly recommended to mitigate this risk.
