Recent articles on some doctors working in their 90s have resurfaced the complex issue of mandatory retirement for doctors (1–3). This question of timely retirement has been debated for many years and is not unique to the medical profession. Industries such as aviation and judicial law have mandatory retirement ages for public safety, acknowledging the detriment of aging on one's performance (4).

With life expectancy increasing, Singapore employees can only be asked to retire at age 64 from 2026, a progressive move towards raising the retirement age to 65 by 2030. As there is currently no mandatory retirement age for doctors in Singapore, how long a doctor chooses to practice is usually a personal choice. This is similar to large countries such as the United States (US), United Kingdom and Australia amongst others (5). Other countries such as China, India, and Russia have established retirement ages ranging from 55 to 65 for doctors (5).

There are a variety of reasons for the mandated retirement ages across countries. In some countries, public service doctors are classified similarly to other civil servants, resulting in blanket retirement ages across all civil service sectors. Mandatory retirement ages for public service doctors also ensures vacancies for new incoming medical graduates entering the system. System-based incompetencies may also hinder the application of competency-based retirement in some jurisdictions. In India and China for example, there are no requirements for license renewal by an independent body. Despite a 2011 resolution by the Medical Council of India requiring doctors to complete 30 h of Continuing Medical Education (CME) every five years to ensure re-registration, only nine of 26 state medical councils have made re-registration for license renewal mandatory, resulting in only 20% of India's doctors following CME rules (6).

Doctors are not immune to age-related physiological decline, leading to concerns that older doctors may compromise patient safety or even cause harm (4). In the spirit of beneficence and non-maleficence described by Beauchamp and Childress (7), patient safety in an older doctor's practice is of foremost consideration. Any doctor's continued practice should be in his/her patients’ best interest and should not lead to any harm.

This essay critically explores this ethical dilemma and examines ways to protect the public and prevent an erosion of trust in the profession.

Medical practice requires a combination of cognitive and physical domains to accurately diagnose and treat patients, and to carry out procedures. Aging and its associated physiological decline may affect a doctor's competency and hamper his/her ability to make sound judgements, thus compromising medical care. A systematic review found that older doctors possess less factual knowledge, are less likely to adhere to appropriate standards of care, and may have poorer patient outcomes compared to younger doctors (21). A US study on doctor age and outcomes in hospitalized older patients found that within the same hospital, patients treated by older doctors had a higher mortality than patients cared for by younger doctors, except for doctors treating high volumes of patients (22).

Advancing age results in difficulties in retrieving known information and learning new abilities (10). With new medical advances and increasing complexities in patient care, CME is widely accepted by the profession as critical to keeping up-to-date with new developments within the medical field (23, 24). Age-related cognitive decline may hamper the ability of a doctor to absorb and retain new information, hindering his/her ability to keep abreast with advancements in diagnosis, treatment protocols, and technologies.

Medical manpower forecasting is notoriously difficult, and the experience in many countries has seen many challenges. At a time when many parts of the world are grappling with a relative lack of doctors, this issue may be further exacerbated if inflexible, mandatory retirement policies for doctors are strictly enforced with no room for competency-based assessment.

An important consideration to take into account when considering whether older doctors should be allowed to practice is setting and specialty. This is particularly pertinent in the fields of surgery and medical specialties which are procedural in nature. These fields require a combination of technical skills requiring dexterity and quick decision-making in an ever-changing environment where unpredictable mishaps may occur.

As discussed above, physiological aging and neurodegenerative disease have significant impacts on cognition and physicality, including aspects such as slowing of processing speed, executive cognitive function, and spatial orientation (31). Thus, older physicians may experience greater difficulty in transforming information to decisions in critical situations, quickly responding to stimuli or handling multiple and complex tasks simultaneously (31). This may pose a danger to patients and adversely affect patient outcomes. For example, a meta-analysis on the association between surgeon age and postoperative complications/mortality found that the mortality in patients undergoing surgery by older surgeons was 1.14 compared to those by middle-aged surgeons and 1.23 compared to those by younger surgeons (33). Anesthesiologists above the age of 65 have also been found to have double the risk of litigation compared to colleagues under the age of 51 (34). However, it must be acknowledged that there are other factors other than age that might contribute to higher litigation rates, such as higher patient volume and complexity of cases.

The above arguments support an older doctor being allowed to practice provided he/she is competent. A mandatory retirement age can be avoided through a combination of complementary measures to certify competence of older doctors. Competence to practice has historically been judged by one's peers, and this should be assessed individually, focusing on functional ability instead of chronological age. A fine balance between preserving patient safety and allowing older doctors to continue medical practice must be achieved.

Current safeguards of patient safety include: 1.

Reactive assessment—doctors can be identified and evaluated after an error has occurred.

In summary, it is important to balance an older doctor's continued ability to practice with the protection of patient welfare. Older doctors who demonstrate that they remain competent despite their age through appropriate assessments should be allowed to remain in practice in the right settings. Rather than imposing a mandatory retirement age, periodic evaluations of clinical ability may offer a more equitable and balanced approach to ensuring patient safety and protecting public trust in the profession.