Quality standard

Quality statement 5: Maintaining plasma lithium levels

Quality statement

Adults with bipolar disorder prescribed lithium have their dosage adjusted if their plasma lithium levels are outside the optimum range.

Rationale

Lithium is effective in treating mania, recurrent depression, and preventing further mood episodes and suicide in adults with bipolar disorder. It has a narrow optimum range, with plasma lithium levels below 0.6 mmol per litre ineffective and plasma lithium levels above 0.8 mmol per litre linked to increased toxicity.

Quality measures

The following measures can be used to assess the quality of care or service provision specified in the statement. They are examples of how the statement can be measured and can be adapted and used flexibly.

Structure

Evidence of practice arrangements and written clinical protocols to ensure that adults with bipolar disorder who are prescribed lithium have their dosage adjusted if their plasma lithium levels are outside the optimum range.

Data source: No routinely collected national data for this measure has been identified. Data can be collected from information recorded locally by healthcare professionals and provider organisations, for example from local medicines policies.

Process

Proportion of adults with bipolar disorder prescribed lithium who had their dosage adjusted if their plasma lithium levels were outside the optimum range.

Numerator – the number in the denominator who had their dosage adjusted if their plasma lithium levels were outside the optimum range.

Denominator – the number of adults with bipolar disorder prescribed lithium.

Data source: No routinely collected national data for this measure has been identified. Data can be collected from information recorded locally by healthcare professionals, for example from patient records. Data can be collected using the NICE menu indicator NM22.

Outcome

a) Adults with bipolar disorder prescribed lithium who have their plasma lithium levels maintained within the optimum range.

Data source: No routinely collected national data for this measure has been identified. Data can be collected from information recorded locally by healthcare professionals and provider organisations, for example from patient records.

b) Kidney function among adults with bipolar disorder prescribed lithium.

Data source: No routinely collected national data for this measure has been identified. Data can be collected from information recorded locally by healthcare professionals and provider organisations, for example from patient records.

c) Thyroid function among adults with bipolar disorder prescribed lithium.

Data source: No routinely collected national data for this measure has been identified. Data can be collected from information recorded locally by healthcare professionals and provider organisations, for example from patient records.

What the quality statement means for different audiences

Service providers (such as GP practices, community health services, mental health services and hospitals) ensure that shared care arrangements, procedures and protocols are in place to adjust lithium dosage and maintain plasma lithium levels within the optimum range for adults with bipolar disorder prescribed lithium.

Healthcare professionals ensure that adults with bipolar disorder prescribed lithium have their dosage adjusted if their plasma lithium levels are outside the optimum range.

Commissioners (such as NHS England area teams, clinical commissioning groups and integrated care systems) specify in their contracts that there are shared care arrangements to ensure that adults with bipolar disorder prescribed lithium have their plasma lithium levels maintained within the optimum range.

Adults with bipolar disorder who are prescribed lithium have regular blood tests to check the amount of lithium in their blood and have their dose changed if they are not getting the right amount to ensure that it is both effective and non‑toxic.

Source guidance

Bipolar disorder: assessment and management. NICE guideline CG185 (2014, updated 2020), recommendations 1.10.15 and 1.10.19

Definitions of terms used in this quality statement

Plasma lithium levels within the optimum range

Plasma lithium levels below 0.6 mmol per litre are ineffective and plasma lithium levels above 0.8 mmol per litre are linked to increased toxicity. Once lithium has been started and stabilised, plasma lithium levels need to be maintained within the range of 0.6 to 0.8 mmol per litre.

If the adult with bipolar disorder needs plasma lithium levels maintained at above 0.8 mmol per litre, they should have their lithium levels monitored at least every 3 months. [Adapted from NICE's guideline on bipolar disorder, recommendations 1.10.15 and 1.10.20]