Serial tests of T-cell function predict long-term survival in an elderly cohort from a Scottish general practice

Area of Science:

• Gerontology
• Immunology
• General Practice

Background:

• Elderly care presents significant challenges in general practice.
• High workload associated with a large elderly patient population prompted research.
• Investigating immune function as a potential factor in elderly health outcomes.

Purpose of the Study:

• To measure serial T-cell function tests in elderly individuals.
• To identify patients with impaired immune responses.
• To assess the long-term impact of immune function on survival.

Main Methods:

• Two-phase research: assessment (1979-82) and long-term follow-up (post-1982).
• Included clinical measurements and immunological tests (lymphocyte proliferation via phytohaemagglutinin - PHA).
• Life-long follow-up of deaths for 246 participants over 36.5 years.

Main Results:

• Factors associated with lower survival included age, male sex, blood pressure, smoking, and poor immune function (failing ≥6 PHA tests).
• Individuals with the poorest immune function had a lifespan 4 years shorter than those with the best function (P<0.01).
• No significant differences were found in GP workload, diagnosed problems, or causes of death between immune function groups.

Conclusions:

• Poor cellular immune function is significantly associated with reduced long-term survival in the elderly.
• A reliable measure of T-cell function is needed for risk prediction in primary care.
• This research highlights the importance of immune status in predicting health trajectories for older adults.