Expenses are charged to the capital account rather than to income, so capital will be reduced. This could constrain future capital and income growth. Income may be taxable.
There is a risk that the issuers of fixed income investments (e.g. bonds) may not be able to meet interest payments nor repay the money they have borrowed. The worse the credit quality of the issuer, the greater the risk of default and therefore investment loss.
The use of derivatives may increase overall risk by magnifying the effect of both gains and losses leading to large changes in value and potentially large financial loss. A counterparty to a derivative transaction may fail to meet its obligations which may also lead to a financial loss.
The value of fixed income investments (e.g. bonds) tends to decrease when interest rates rise.