A method and system for detecting insulin resistance, diabetes, cardiovascular disease and/or autonomic neuropathy in a patient is provided. The method includes measuring a photoplethysmogram (PTG) and galvanic skin response from the patient, executing a spectral analysis on the PTG, comparing values derived from the PTG and the galvanic skin response of the patient to stored clinical data, calculating a PTG cardiovascular risk score based on the comparison, comparing further derived values to predefined values that correspond to certain diseases, including insulin resistance, diabetes, cardiovascular disease and autonomic neuropathy, and displaying the PTG cardiovascular risk score and said certain diseases that correspond to said predefined values.