Bipolar Disorder (BD) can seriously impair a person’s life if not effectively treated. Lithium (Li) offers the most successful long-term management of BD, but it entails a considerable risk to the patient if not closely monitored to ensure concentrations are maintained within its narrow therapeutic range. Unfortunately, poor patient compliance with regular blood tests and high rates of treatment non-adherence often result in illness relapse. At higher concentrations lithium is toxic and can cause serious complications that can be fatal.
Here we propose a method to be used in a personal lithium analyser that will potentially be of great benefit to patients by:
- Enabling more active patient involvement in the management of their illness,
- Improving adherence and
- Reducing risk of toxicity through early detection of lithium concentration shifts.
The working principle of the analyser is based on a novel multimodal sensing technique that combines optical spectroscopy and electrical impedance measurements, which together offer a high degree of selectivity and sensitivity for rapid and accurate detection of blood lithium concentrations.
The study investigates the feasibility of opto-impedance measurements in in vitro samples of human plasma using both qualitative and quantitative analysis techniques. The prediction accuracy is also examined through validation tests that were performed on blood samples with unknown concentrations of lithium.
The proposed method showed significant improvement in both calibration and prediction models, when compared to optical measurements alone, as well as enhanced prediction capabilities of lithium levels in validation test samples and reduced error of measurement between samples.
The results indicate that the proposed opto-impedance method can be a suitable working principle in a personal lithium analyser, which could benefit many Bipolar patients and indeed improve their long-term treatment. The outcome also highlights the enormous potential that medical devices have for assisting mental health conditions.