Recent studies confirm that older divers may be
more susceptible to severe decompression illness
(DCI) than younger ones, and less able to recover.
Divers Alert Network (DAN) compared cases of diving
fatalities with divers from Project Dive Exploration
to explore potential risk factors in diving.1
Potential risk factors tested included: age, gender,
body mass, smoking, asthma, diabetes, cardiovascular
disease, years since certification, dives last year, last
dive depth, Nitrox use, and dry suit use.
Those factors that suggested an increased risk
were: a significant increase in body mass, smoking,
diving 50 ft. deeper than on one’s last dive, and a 20-
year increase in age. (Risks of deaths from asthma,
diabetes, and cardiovascular disease also increased
with age.)
Divers with reduced risk were those diving less than
10 years since certification, making more than 30 dives
in the last year, and using dry suits. DAN pointed out
that these factors showed an association, not causality.
The University of Hawaii reviewed 889 cases
treated for DCS at the school’s Hyperbaric Treatment
Center. The preponderance of injuries occurred in
divers 21-40 year old. Of 889 cases, 250 were severe
and 58 (23.2%) of those did not achieve complete functional recovery as compared with 0.5% of mild to
moderately severe cases. 2
Age |
% of Severe Cases |
Incomplete recovery |
under 20 |
31.9% |
20.0%, |
21-30 |
21.9% |
19.3% |
31-40 |
26.0% |
21.6% |
41-50 |
31.4% |
30.6% |
51-60 |
45.0% |
29.6% |
over 60 |
60.0% |
44.0% |
Researchers concluded that the degree of DCI
severity portends poorer outcomes, and it becomes
more pronounced with advancing age. While it
appears that older divers are no more likely to incur
DCI because of their age, their cases may be more
severe and they are less apt to recover completely.
1. Case Control Analysis of Diving Fatalities, Dear GD, Caruso JLA,
Denoble PJ, Department of Anesthesiology, Duke University;
Freiberger JJ, Pieper CF, Center for Hyperbaric Medicine and
Environmental Physiology, Duke University Medical Center,
Durham, NC; Vann RD, Divers Alert Network (DAN), Durham, NC.
2. Effect of Aging on Prevalence and Recovery from DCI, Smerz RW,
Hyperbaric Treatment Center, University of Hawaii, John A. Burns
School of Medicine, Honolulu, Hawaii.