diff --git a/freqtrade/optimize/analysis/lookahead_helpers.py b/freqtrade/optimize/analysis/lookahead_helpers.py
index 1d2b9db48..00f83a46b 100644
--- a/freqtrade/optimize/analysis/lookahead_helpers.py
+++ b/freqtrade/optimize/analysis/lookahead_helpers.py
@@ -107,9 +107,9 @@ class LookaheadAnalysisSubFunctions:
                 csv_df = add_or_update_row(csv_df, new_row_data)
 
         # Fill NaN values with a default value (e.g., 0)
-        csv_df['total_signals'] = csv_df['total_signals'].fillna(0)
-        csv_df['biased_entry_signals'] = csv_df['biased_entry_signals'].fillna(0)
-        csv_df['biased_exit_signals'] = csv_df['biased_exit_signals'].fillna(0)
+        csv_df['total_signals'] = csv_df['total_signals'].astype(int).fillna(0)
+        csv_df['biased_entry_signals'] = csv_df['biased_entry_signals'].astype(int).fillna(0)
+        csv_df['biased_exit_signals'] = csv_df['biased_exit_signals'].astype(int).fillna(0)
 
         # Convert columns to integers
         csv_df['total_signals'] = csv_df['total_signals'].astype(int)