Our study aims to determine the incidence of undiagnosed and poorly controlled diabetes among surgical patients in Singapore using preoperative HbA1c as a screening tool.

The study aims to determine the incidence of undiagnosed and poorly controlled diabetes among surgical patients in Singapore using preoperative HbA1c as a screening tool.

The investigators aim to follow up on the incidence of perioperative complications in this cohort. In the longer term, the investigators hope to evaluate the role of a preoperative diabetic screening and intervention program as an opportunistic "teachable moment" for surgical patients. This may help to achieve greater control of the disease burden in Singapore.

Specific aims:

Specific Aim 1: To establish the incidence of undiagnosed diabetes/prediabetes among surgical patients in Singapore, based on HbA1c level ≥ 6.1% prior to surgery Specific Aim 2: To establish the incidence of poorly-controlled diabetes among surgical patients in Singapore, based on HbA1c level ≥ 8% prior to surgery Specific Aim 3: To identify and characterize any association between preoperative HbA1c level and postoperative outcomes

Inclusion Criteria:

1. Age >21 years old
2. able to give informed consent
3. Scheduled to have preoperative blood taken during clinic visit

Exclusion Criteria:

1. Age < 21 years old
2. unable to given informed consent
3. Not required to have routine preoperative blood tests taken

All patients who comes through the pre operative anesthesia clinic due to scheduled elective operation, who fits the inclusion criteria of the study.