Type 5 diabetes: a 70-year perspective and its implications for the Americas.

Area of Science:

• Endocrinology
• Metabolic Diseases
• Global Health

Background:

• Type 5 Diabetes (T5DM), initially identified as J-type diabetes, presents a unique clinical phenotype distinct from other diabetes forms.
• Key characteristics include low body mass index (<18.5 kg/m²), low hepatic fat mass, low C-peptide, normal insulin sensitivity, and absence of ketoacidosis.
• Despite its distinct profile, T5DM is frequently misdiagnosed or overlooked, leading to unknown underreporting rates.

Purpose of the Study:

• To commemorate the 70-year history of Type 5 Diabetes (T5DM), originating in the Americas.
• To emphasize the distinct clinical characteristics of T5DM.
• To advocate for increased focus on this underdiagnosed condition, particularly in regions facing nutritional challenges.

Main Methods:

• Historical review of Type 5 Diabetes (T5DM) identification and reporting.
• Analysis of common clinical features distinguishing T5DM.
• Discussion of epidemiological context, including nutritional transitions and undernutrition in the Americas.

Main Results:

• T5DM was first described in Jamaica in 1955 and has since been reported globally.
• The unique phenotype of T5DM includes specific anthropometric, metabolic, and biochemical markers.
• Chronic undernutrition in parts of Latin America and the Caribbean may increase the risk of T5DM.

Conclusions:

• Type 5 Diabetes (T5DM) represents a significant, yet underrecognized, diabetic subtype with a distinct phenotype.
• The condition's origins in the Americas and its association with undernutrition warrant focused research and clinical attention.
• Refocusing efforts on T5DM is crucial for accurate diagnosis and management, especially in vulnerable populations.